High ms ticks in 1.14+, player cannot interact with world normally

When placing or destroying water, there's a 27 second delay. 

If you hit a villager & then place a block, the hit is delayed, & you will be pulled back to the block repeatedly when you try to walk away.

Destroyed leaved & logs sometimes reappear after being destroyed. 

Seems to affect block entities, e.g. chests, anvils, switches, etc., but not blocks. Doors and trapdoors are fine. Also affects picking up items. Teleportation results in "rubberbanding". Also seems to affect the generation of certain chests in ruins and shipwrecks, they're generated empty. Furthermore affects the pointer on maps updating its position.

Seems to affect creative mode more than survival mode, and it affects switching gamemodes too.

And it affects monsters. A creeper just moved to an old position where I was several seconds ago, exploded and the explosion hurt me, even though I was about fifteen blocks away. Same with skeletons shooting at former positions and hitting me. Also affects crossbows.

Next function affected: Falling damage and Elytra.

I experienced an issue with the crafting table interface. I started a world in the previous snapshot, backed it up and loaded it into the newest snapshot, and the crafting table interface is out of whack. Takes quite a few seconds to open, rejects anything I place in it (the items get sent back into my inventory after a second or two), and repeatedly re-opens whenever I close it. It even interferes with the in-game menu (with the settings, bug report, save/exit, etc. buttons) by exiting it. Playing on MacOS High Sierra and in creative mode. 

I can confirm @unknown's observations, with the addendum that it does also affect blocks that the player is mining, especially if it drops an item to pick up.
 
 

i did /kill and it took 5 minutes fro that to load then when i try to click respawn it does nothing. i have reset my computer and relogged many time but still my character does not respawn and the screen seems to be shaking. Any suggestions?

affect 18w45a

Ill add some info that ocurred to a friend.

He have this issues on an intel laptop(old gen one),Im not getting this issue(ryzen 2700)

This maybe caused by CPU/threads, can someone change afinity of minecraft to only true cores?

I am having this issue as well. I hit a mob and wait 1 minute. It takes 2 minutes to open a chest and when it does open anything I take from it glitches back into it if I open another chest. Very annoying.

Still active, affects 18w47a.

Duplicated by MC-139850 and MC-138114.

I cannot attack any entity for several seconds. Annoying attack indicator says it's loaded, keeps loading, no result. Sometimes, game would crash after clicking on villager. So Annoying!

I post some update and how(probably) get rid of the ms world/entity lag,

If u have a intel cpu, change the afinity to true cores(1,3,5,etc).This worked on the machine of my friend, he can now play normaly.

I still to this current snapshot dont have any issues with world/entity lag.(i have a ryzen 2 cpu).

Can someone confirm this?

Same as MC-138114

Confirmed in 18w48a, 18w48b, 18w49a and 18w50a

This can cause blocks to disappear. I mined a block of stone, it disappeared without dropping itself as an item. A few seconds later, the block reappeared, and a few seconds after that the block finally disappeared again, still without becoming an item. I checked my inventory and it was not there. I checked the surface above the cave (only 3-4 blocks to the surface) and the block wasn't there. I quit and reloaded the world and the block was still nowhere to be found.

Not that I care much about a block of stone, but I had to verify for myself that the block actually disappeared, because it's good to know. If this happened with a block of diamond I'd be pretty upset!

What I've found is similar to what others have found, and it's a problem that affects the game experience. I hope this problem can be solved as soon as possible

This issue is very serious and has been around for a while? Shall Mojang be jumping in to fix the issue for the next snapshot.

Not sure if it's just me, but this problem is WAY worse in 19w05a.

I just had this happen to me as well in a single player world in survival mode.  I cut down a series of trees in a row, heard the block break plop sound... but no logs on ground or inventory.
save and exit game is now still locked up 15 minutes+ after initiating the exit.
Side note, item pickup has been seen delayed as well (when trees dropped logs still).

Edit: version 19w05a , log file does not contain recent information, last entry was from ~5 minutes before I logged out when I toggled the hitboxes on (F3+B)

This issue is gotten worse in 19w05a especially in the end.

Sometimes I'm climbing down a ladder and it lags, and after a few seconds of getting to the bottom I take fall damage as if I had fallen off the ladder. It's usually only a little bit of damage, but it just happened again and I took 4 hearts of fall damage – entirely due to lag!

Confirmed in 19w07a. Why mojang did not fixed this annoying bug ?

What is required to reproduce this?

I haven't experienced this before.

@Doubletoad74 , have a intel cpu(suspecting of a movile one(laptop))

Confirmed in 19w08a.

Confirmed in 19w08b and 19w09a.

I wonder if it has to do with world size. I was playing on the 19w08b snapshot prior to 19w09a with no issue. When I updated to 19w09a, I still had no issue. At this time, my world save file was relatively small. When I updated I decided to do a bit of creative flying to look for Pillager Outposts.

I stopped after awhile. Now, my current world save file size is almost 1GB. after about the 500MB mark, I noticed my world started to have issues with chunk loading for new chunks, and trying to respawn took ages.

Upon starting a new world on 19w09a, I dont have any of these issues.

So I am curious what the save file size is of others reporting this issue. It would seem like the integrated server is having the same kind of problems handling large worlds that a normal server would if it lacked proper resources.

Now, I launch the game with a 6GB ram allocated to Minecraft, and I dont use mods. My CPU is an i7-3700 quad at 3.4ghz....so old, but more than enough to even run modern games.

This tells me that there is something wrong coding wise with the integrated server, likely with how resources are allocated. An immediate fix would simply be removing the integrated server....cause well, we dont need one in SP, and MP has a dedicated server system. 

I believe this is fixed in the latest snapshot due to the fix of MC-138071.

Is this still an issue in 19w11b? If it's still an issue, please provide reproduction steps.

I tried to spawn 100 entities(+naturally-spawned ones) in the classic superflat world. On 1.13.2 and 1.12.2 tickrate is higher than the snapshots. Same with the datapacks.

(In 1.13.2 my datapack works pretty well (as it can), but on the snapshots TPS graph goes above the stratosphere).

So, subjectively, i think the problem is still here, but also i think somebody else should check this out and make some measurements too...

I attached some of the new logs to the report.

When I use an end gateway it no longer lag since 19w11a It's maybe with the fix of MC-138071 or I don't know.

@unknown, those logs appear to be for 18w45a. Can you check 19w11b? There were definitely issues back in 45a but those are possibly fixed now.

Oh, lol, my bad. I accidentally named the files "18w45", but it's, of course, 19w11b snapshot debug logs 😃

it's still in the latest snapshot, 19w12b

After short duration of playtime I've noticed that the tick execution time rises continuously until the game starts to compensate by massively slowing down chunk loading, world interaction, physics, and eventually skipping ticks. This appears to be the exact same case for a lot of the previous snapshots, including 19w13.

5 minutes of exploring:

15-20 minutes of exploring:

Abnormal execution time (happens rarely, complete world reload / server restart is required to fix it):

The gradual increase makes me think this may have something to do with the tick idle time?
Also MC-138114, MC-132135 and MC-139717 might be related.

Confirmed for 1.14 Pre-Release 1 and Pre-Release 2.

Please attach the file generated by

/debug start

, waiting a few minutes, and

/debug stop

when you're experiencing low tickrates, along with an explanation of where you are and what you were doing.

These two debug logs are from different locations in a new world generated on 1.14 pre-2, exploring around a bit in creative mode, visiting structures (mostly villages, pyramids, ocean ruins, etc.) and staying in different places for a while. Noticed very bad periodic TPS drops and consistently high execution time, along with the server completely hanging for 10-20 seconds once in a while, most likely due to autosave. This was exceptionally worse throughout the second logging period.

1.14 has clearly some FPS and "Chunks loading" issues. Feels like 1.14 was released too early. Hope you guys can fix it so it will be playable like 1.13.2!

FPS has nothing to do with high ms ticks. By chunks loading issues in 1.14, I suppose you meant the issue with chunks rendering in a non seamlessly manner, but that's already been fixed for future release.

a thing that might be noteworthy: from personal experience, it seems that the chunk rendering is significantly more smooth and less laggy by using the loopback adress of the server rather than the public one.

Attached another debug output log file - most of the time logged in that debug output was me standing still attempting to eat. There was the remainder of a pillager raid with a few pillagers in a village near the spawn of the world, but things were so slow, it was impossible to do anything - move, fight, eat, anything.  CPU and RAM usage of the server were low - only about 1 GB of RAM used, and about 30% CPU usage, so it's not a resource availability issue.

When you hit a mob, it will be delayed. It will fly for a few seconds before landing.

Updated client and server to 1.14.1-pre1, and can see a noticeable improvement, though still not even hitting 20 TPS with only a single client connected.  Attached debug capture with myself connected with a Vanilla 1.14.1-pre1 client.  Time was spent walking through a cave system that is probably just outside of the spawn chunks of the world, breaking some blocks, placing torches, and encountered a couple of hostile mobs (some silverfish, a couple zombies, and a creeper).  There was the sound of a skeleton, but it never appeared in my vision, so may have been on the other side of a wall.

I did encounter some block lag where a block would be broken, re-appear, then disappear again and drop its item. When attacking the silverfish, there were times when the mob would stall for a moment not moving, and also the hitbox was out of place with where the rendered model was showing on the screen, causing some sword swings to miss that I would have expected to hit. One of the zombies did show the clear stutter-step pattern of the server struggling to position it and move it, but that cleared fairly quickly.

Not entirely fixed, but definitely an improvement over 1.14.

Improvements appear to be limited to just having a single player on the server.  The instant a second player joined the server, performance went right back down the tube (7 TPS).  I was in the same cave system as during the previous debug capture, and noticed that hostile mobs were having severe difficulty with navigation, and were rubber banding, stuttering, and freezing in place.  The second player on the server was in a boat, and at one point fell through their boat, through the water, and down into a cave underneath the water about 20 blocks.  Pulled another debug log, and attaching it here.

Looking at the debug log files, the only thing that sticks out is the very high percentage of tick time being spent on AI for the various entities in the loaded chunks, particularly cod, but given that everything is in averaged percentages, it is impossible to tell with that information alone just how much actual time is being spent where. System resource usage on the server is still well below any sort of threshold value - CPU is running around 30%, and RAM is under 1 GB used.

Just entering my old world made it unplayable by the lag, when creating new ones the game runs fine. 

That bit about new world vs upgraded world does not apply to 1.14 at least. Have not tried a newly created 1.14.1-pre1 world. The 1.14 captured debug logs from me earlier are from a fresh 1.14 world, not upgraded from a previous version.

Loaded up a brand new world in 1.14.1 pre-release 1 and began loading chunks. I was able to outrun chunk loading in a boat, but the server seemed to be fairly stable. I jumped into creative and started flying in a straight line, and chunk loading could not keep up. I began getting really bad rubber banding. I landed and stopped moving and later the server crashed because a single tick took over 60 seconds.

Attached file is a debug session from flying in a straight line into ungenerated chunks.

Affects 1.14.1-prerelease-2

Was fighting drowned in some ocean ruins when my server crashed. Restarted the server, and captured this debug session fighting the drowned.

Obviously, not everyone is affected by the performance issues in the same manner. It would be useful if you include extra informations with the debug profiling for any report you make:

• If you are on server, your host specifications and your JVM arguments.

• If you are on singleplayer, a complete screenshot of your screen in F3 mode with profiler graphs shown (alt + F3).

If, like me, you're on a server hosted by a dedicated hosting provider, we do not have access to the JVM arguments that are being used, and I have had zero luck getting their support people to tell me what they're using.

This issue is very apparent on anyone that runs a minecraft server regardless of the specs. I have this issue on a i7-6700K 32GB RAM 240GB SSD server with a single player on. My TPS drops below 10 randomly and the error appears. I have seen it many times.

I noticed 1.14 and 1.13 are more resource demanding than 1.12 and before. But I mostly don't experience this high ms tick issue under normal survival gameplay.
I have a 8x3.5Ghz CPU, 32GB RAM, and SSD. My JVM arguments follow the recommendations for optimal garbage collection (not endorsed by Mojang, use at your own risks). My view distance is currently 8.
The only significant and recurring circumstance when I experience this issue is right on time whenever someone uses a Nether Portal MC-117914.

i can still interact with the world and i don't receive console warnings, but i still think the problem is related to this htread so here we go:

i'm on a singleplayer world.

since 1.14.1 pre-2, there is a return of the lag, from 1.14 release for me (1.14 pre5 was fine, and 1.14.1 pre1 is also fine)

what  happens is after a few minutes, the game become very choppy when interacting with blocks (cutting logs and even getting loot from the ground)

in debug windows, i can see huge spikes on the fps graph

i also see that when turning around in 360 circles rapidly, the chunk update counter goes through the roof until it goes up to around 200 and keep there as long as i continue turning to fall back to 0 if i stop.

just to be sure, i reloaded the world with the same parameters (made a copy of the profile) to the 1.14.1 pre1 and sure enough i don't have the choppiness problem, and i also don't have any spike in chunk updates when turning around in circle.

Running the latest snapshot, using a dedicated server i7 4790k @4GHz, 32GB RAM, 280GB SSD.
With only 5 players on the server, I'm getting 17.5TPS.

My startup script:

java -Xms10G -Xmx10G -jar server.jar

My results: 

EDIT:

I have had a lot of bugs too:

• multiple wandering traders naturally spawn https://vimeo.com/335597417 

• no hostile mobs, then when I save and reload there are so many of them

• takes a lot longer for me to eat / can't eat https://vimeo.com/335597417 

• Leads don't break https://imgur.com/a/vssjAwG (I shouldn't even be able to leash a wandering trader llama who is leashed to an owner, right?)

Turns out my tps is 10.8

When will this bug be patched? It annoys me.

Ok i might've found a solution that at least worked for me. If you are hosting this on the same network then you will have to use to local IP to connect to your server. i changed this and immediately everything cleared up.

1.14.1 still encountering lag issues.

1.14.1

Same issue, ticks per second 10.6

This bug still exists in 1.14.1, this is a big issue in servers aswell. For no reason the server can get lagspikes and mobs also jitter even if the server has enough memory.

I have the issue in 19w08b - Sometimes when I teleport, the chunks aren't generated, and I fall into the void.

1.14.1

My debug file

[19:18:18] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 1955.059163 ms
[19:18:18] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 1976.44575 ms
[19:18:18] [Server thread/WARN]: Something's taking too long! 'root' took aprox 1978.03841 ms
[19:18:18] [Server thread/WARN]: Something's taking too long! 'root' took aprox 112.751481 ms
[19:22:09] [Server thread/WARN]: Something's taking too long! 'root.nextTickWait' took aprox 232.150524 ms
[19:22:09] [Server thread/WARN]: Something's taking too long! 'root' took aprox 274.159844 ms
[19:22:34] [Server thread/WARN]: Something's taking too long! 'root' took aprox 123.574365 ms
[19:22:34] [Server thread/WARN]: Something's taking too long! 'root' took aprox 112.637989 ms
[19:22:34] [Server thread/WARN]: Something's taking too long! 'root' took aprox 104.883023 ms
[19:23:17] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 1193.393295 ms
[19:23:17] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 1233.593166 ms
[19:23:17] [Server thread/WARN]: Something's taking too long! 'root' took aprox 1262.187443 ms
[19:23:41] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 324.348277 ms
[19:23:41] [Server thread/WARN]: Something's taking too long! 'root' took aprox 325.012467 ms
[19:23:47] [Server thread/WARN]: Something's taking too long! 'root.nextTickWait' took aprox 135.755801 ms
[19:23:47] [Server thread/WARN]: Something's taking too long! 'root' took aprox 171.469419 ms
[19:24:29] [Server thread/WARN]: Something's taking too long! 'root' took aprox 119.049977 ms
[19:24:36] [Server thread/WARN]: Something's taking too long! 'root.nextTickWait' took aprox 170.370536 ms
[19:24:36] [Server thread/WARN]: Something's taking too long! 'root' took aprox 205.543931 ms
[19:24:36] [Server thread/WARN]: Something's taking too long! 'root' took aprox 122.043444 ms
[19:26:28] [Server thread/WARN]: Something's taking too long! 'root.nextTickWait' took aprox 105.723004 ms
[19:26:28] [Server thread/WARN]: Something's taking too long! 'root' took aprox 142.745935 ms
[19:27:01] [Server thread/WARN]: Something's taking too long! 'root' took aprox 119.206421 ms
[19:28:17] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 1701.125213 ms
[19:28:17] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 1740.485662 ms
[19:28:17] [Server thread/WARN]: Something's taking too long! 'root' took aprox 1744.666431 ms
[19:29:11] [Server thread/WARN]: Something's taking too long! 'root' took aprox 104.654083 ms
[19:29:22] [Server thread/WARN]: Something's taking too long! 'root' took aprox 103.925639 ms
[19:29:24] [Server thread/WARN]: Something's taking too long! 'root' took aprox 100.48365 ms
[19:29:51] [Server thread/WARN]: Something's taking too long! 'root' took aprox 100.126972 ms
[19:31:04] [Server thread/WARN]: Something's taking too long! 'root.nextTickWait' took aprox 178.615159 ms
[19:31:04] [Server thread/WARN]: Something's taking too long! 'root' took aprox 215.048211 ms
[19:32:52] [Server thread/WARN]: Something's taking too long! 'root' took aprox 102.229613 ms
[19:33:18] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 2139.701834 ms
[19:33:18] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 2187.11631 ms
[19:33:18] [Server thread/WARN]: Something's taking too long! 'root' took aprox 2238.956558 ms
[19:33:18] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 2190ms or 43 ticks behind
[19:37:05] [Server thread/WARN]: Something's taking too long! 'root' took aprox 100.226915 ms
[19:37:44] [Server thread/WARN]: Something's taking too long! 'root' took aprox 111.856185 ms
[19:38:19] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 953.942051 ms
[19:38:19] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 990.939351 ms
[19:38:19] [Server thread/WARN]: Something's taking too long! 'root' took aprox 996.574075 ms
[19:43:16] [Server thread/WARN]: Something's taking too long! 'root' took aprox 102.161378 ms
[19:43:19] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 771.84698 ms
[19:43:19] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 827.528289 ms
[19:43:19] [Server thread/WARN]: Something's taking too long! 'root' took aprox 856.426096 ms
[19:43:43] [Server thread/WARN]: Something's taking too long! 'root' took aprox 100.993352 ms
[19:43:48] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 2001ms or 40 ticks behind
[19:43:53] [Server thread/WARN]: Something's taking too long! 'root' took aprox 119.861952 ms
[19:44:07] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 3782ms or 75 ticks behind
[19:44:09] [Server thread/WARN]: Something's taking too long! 'root' took aprox 109.270941 ms
[19:44:18] [Server thread/WARN]: Something's taking too long! 'root' took aprox 120.934015 ms
[19:44:27] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 5414ms or 108 ticks behind
[19:44:48] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 5264ms or 105 ticks behind
[19:44:51] [Server thread/WARN]: Something's taking too long! 'root' took aprox 125.0154 ms
[19:44:56] [Server thread/WARN]: Something's taking too long! 'root' took aprox 112.915608 ms
[19:45:08] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 5097ms or 101 ticks behind
[19:45:27] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 3886ms or 77 ticks behind
[19:45:46] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 4049ms or 80 ticks behind
[19:45:50] [Server thread/WARN]: Something's taking too long! 'root' took aprox 107.851976 ms
[19:45:58] [Server thread/WARN]: Something's taking too long! 'root' took aprox 110.245785 ms
[19:46:05] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 4318ms or 86 ticks behind
[19:46:19] [Server thread/WARN]: Something's taking too long! 'root' took aprox 107.212928 ms
[19:46:24] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 3825ms or 76 ticks behind
[19:46:35] [Server thread/WARN]: Something's taking too long! 'root' took aprox 118.655304 ms
[19:46:37] [Server thread/WARN]: Something's taking too long! 'root' took aprox 122.593305 ms
[19:46:43] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 3955ms or 79 ticks behind
[19:46:50] [Server thread/WARN]: Something's taking too long! 'root' took aprox 125.057445 ms
[19:47:02] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 4333ms or 86 ticks behind
[19:47:18] [Server thread/WARN]: Something's taking too long! 'root' took aprox 101.522051 ms
[19:47:22] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 2024ms or 40 ticks behind
[19:49:07] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 1218.580085 ms
[19:49:07] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 1254.495753 ms
[19:49:07] [Server thread/WARN]: Something's taking too long! 'root' took aprox 1263.584199 ms
[19:54:06] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 669.257126 ms
[19:54:06] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 704.004839 ms
[19:54:06] [Server thread/WARN]: Something's taking too long! 'root' took aprox 706.719988 ms

This seems to occur even on a brand new world, but only in 1.14.1. 1.14 is completely fine. The server just suddenly starts lagging like crazy, kicking everyone out and crashing because the ticks take too long. This can happen after anywhere between 5 minutes and 1-2 hours of the server running. But i haven't gotten it to run for more than about 2 hours max before crashing. With max-tick-time set to 1 it won't crash the server but instead kicks everyone out and after about 5-10 minutes people can join again. A few days ago i uploaded a debug log. If need be i can provide more.

My experience, as shown by the multiple debug logs attached previously, definitely do not match Carl's description above - I see this issue on 1.14, 1.14.1-pre1, 1.14.1-pre2, 1.14.1, and now also 1.14.2-pre1.  Given that there were no mentions of anything that appeared to be performance related in the release notes, I'm not surprised this prerelease hasn't addressed any of the potential underlying causes for this issue.

Here is the most recent debug output for 1.14.2-pre1: 

Top tick usage is entities, and still seeing AI very high on the list with mobs that exist in large quantities like cod.

Still a major problem in 1.14.2 Pre Release 1. I'm hosting through MCProhosting - displaying at 100% CPU with 4 players on, almost always at 100% with just two players. It is borderline unplayable at times.

Experiencing the same on 1.14.1. My server would just sit idle and then start throwing  

Can't keep up! Is the server overloaded? Running 2407ms or 48 ticks behind

It's currently unplayable. Have to restart the server every 5 minutes if we're more than 1 playing, and it doesn't help increasing ram constraints.

same issue on 1.14.1 sometimes over 4300ms behind

Through Minecraft-hosting.pro, I do not see the CPU as being pegged (which is honestly the thing that makes this whole situation more baffling), but still seeing severe issues with 1.14.2-pre2 even with just a single user logged in to the world.  The most detailed information I can give you regarding the environment is as follows:

CPU: E3-1240v2 - 3.8GHz

RAM: 4 GB

Storage: SSD (no clarification if this is NVME vs. standard SSD; suspect standard)

Most recent debug log: 

What was going on: Single player in underground cavern doing some minor caving activities including: breaking various stone type blocks, encountering a handful of hostile mobs (zombies, skeletons, creepers), placing torches, creating new torches via 2x2 inventory grid.

Observed behavior: Block lag, mob pathing and movement issues, creeper explosion lag, hitbox detection issues (swing a weapon where an enemy should be based on client rendering, does not hit).

Server was sitting idle this morning with no players online. I started debug profiling, and after invoking /seed command got the following logs

[06:59:38] [Server thread/INFO]: Seed: [-8299205347331588351]
[07:01:07] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 144.547299 ms
[07:01:07] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 170.993653 ms
[07:01:07] [Server thread/WARN]: Something's taking too long! 'root' took aprox 171.328691 ms

I then listed players and 3 minutes later, still with no one playing got the same tick warnings.

[07:03:02] [Server thread/INFO]: There are 0 of a max 5 players online: 
[07:06:07] [Server thread/WARN]: Something's taking too long! 'root.tick.save' took aprox 124.181894 ms
[07:06:07] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 146.617086 ms
[07:06:07] [Server thread/WARN]: Something's taking too long! 'root' took aprox 146.842638 ms

After ending debug server indicated 20,00 ticks per second. See attached logs

[07:06:47] [Server thread/INFO]: Stopped debug profiling after 578.45 seconds and 11570 ticks (20,00 ticks per second)

It's gotta be at least partially environmental; as a test, I loaded up the 1.14.2-pre2 server on my local PC:

Core i5-7600

16GB DDR4 RAM

Minecraft world running from standard platter HDD

64-bit Java:

java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)

Running under Windows 10 Home edition.

With one exception, I have seen none of these same problems in this environment. Shortly after setting it up during a test run with me and a friend both connected via clients on other machines, and both remote on separate networks, we hit one lag spike that kicked us both, but I did not have the debug log running.

[15:59:06] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 40905ms or 818 ticks behind

And then both remote connections were dropped.

Since that time, one or both of us have been on pretty much constantly, and there have been no signs of the "can't keep up" messages that I am seeing on the hosted server whose specs I included earlier. There are a lot of unknowns with my current server host, and since they refuse to interact with me, I can't find answers to them (for example - what OS the machines are running, what specific version of Java beyond just some flavor of 8, what JVM command arguments are being used, etc).

Especially given that the hardware resource monitor on the hosted environment never shows the CPU or RAM usage coming anywhere close to capacity, this doesn't seem like it should be a hardware capability issue. Given the breadth of reports of this issue that I'm seeing across the community, and from responses that I've gotten from multiple other server hosting sites, something is clearly going on.

If there is anything we can provide beyond just these debug logs to try and get to the bottom of this, please let us know because this is extremely painful, and the silence coming from Mojang on this issue is deafening. There has not been a peep of attempting to address these issues in the recent release notes, and this ticket is getting zero responses or updates either.

Added another debug log - this issue desperately needs addressing. Using the Witch Plan on MCProhosting, has 4GB of RAM and gives slots for 70 players - the server is maxing out at 100% CPU and flooding the console with "Can't Keep Up!" errors with just TWO players on.

I managed to fix my problems i mentioned a few comments above. I did so by installing every single windows update there was, defragmenting my hdd and reinstalling java. This might not help any of you at all but it might be worth a shot for those of you running on windows and not through some hosting site. I might just be lucky or maybe my issues were unrelated but thought i would share anyway. After doing these steps the server ran the whole day yesterday without crashing or freezing or kicking anyone out.

I can confirm this issue.

Causes extreme lag and server shut-downs. Very frustrating, lost hours to tracing issues.

I have attached debug traces and crash reports.

^

^

^^

^^

Can this be broken raids behavior? entities seems high. maybe its posible that multiple raids geting trigered while exploring and starting atack and activating mob ai? maybe they get stuck maybe theyr interaction activating those chunks? maybe those entities dont get removed? maybe they keep spawning again and again? no realy i dont like raid update, its realy complicated to make and stupidly hard maybe imposible. Raid entities newer get removed? so they there all the time in memory? maybe? maybe they still got mob ai?
maybe mob is stuck in air/water and keeps jumping because ai to get in perfect location?
I dont realy know maybe my speculation can help?

Guys make a test without villages and see how that impacts performance so its easyer to find cause of isusue.

I have /kill all mobs related to villagers type by type and all at once and have only seen a minor improvement. I do not believe this is related entirely to the new villager mechanics.

okay sounds like unloading chunks causes huge integrated server spikes. Loading them has no effect on integrated server tps.
1.14.2 PRE 2 Vilages are turned off

78ms spikes

I upgraded my server to 3 times the amount of ram (had it stupidly set to 2GB of ram on OSX) and ran it with the gui enabled.

I could see that garbage collection was happening frequently and I didn't see the server ever falling behind. Ticks stayed around 3-7 average, but still had some blocks re-appearing, not sure what caused that, as I'm connecting locally while my friends are remote.

My problem was definitely a configuration one and not a fault in the code. Ran the server on both OSX and lubuntu and had no problems.

I went with the server requirements posted on the gamepedia website. It's also notable that these are the requirements just for the server to run and not including OS resources.

Dedicated Server Requirements

@jokubas

I don't think that synthetic tests are very useful in this instance as I don't think we should be ruling anything out. I have seen reports that overhead per villager is ten times that of 1.13, and that sounds like an unintended impact of the new villager code. As someone administrating a server impacted by this issue I can say that we'd like the villager impact assessed as part of this as we have a 40 villager iron farm in the spawn chunks (we haven't implemented a perma-loader yet because we're waiting to see what the final word from Mojang on this issue).

@Neil Hogg

You indicate that you tripled your RAM from 2GB to 6GB, for how many users? 4 to 8, by my guess?

If so, this is (historically) an insanely high amount of RAM for so few users. It might be the case that Minecraft's efficiency has tanked that far, but if that's the case then Mojang need to update their guidance on server configuration, because they are still claiming that 1GB is sufficient for a low user count server. If 4GB is no longer sufficient for hosting our server I want to know about it because it will cause me to seriously re-evaluate our hosting strategy and hosting hardware. If I am going to commit to a significant purchase of a faster CPU and a lot more RAM (and a motherboard to house them) then I need to hear it from Mojang.

I suspect that the issue is somewhat situational. Last night I was experiencing this issue on our server to the point it was causing the watchdog to shut down the server. I was able to work through the issue by moving through chunks until the one causing the problem to close the server was loaded, at which point I immediately logged out (I was the only person on the server at the time). By doing this several times I was able to 'unjam' the chunks. This is not to say that the issue isn't impacting us all the time, more that when it progresses to the point it abends the server I was able to get the server to work through the logjam of processing by using the chunk unload delay to get the chunk to be processed without the additional overhead of having a player actively logged in and interacting with the world. I also found that triggering a graceful server shutdown while the server was ticking behind would also resolve the issue in some cases.

I am inclined to believe that there is something very stupid in the 1.14 code. If we're lucky it's some badly written code that can be addressed to reduce the overhead, but I am increasingly worried that the issues are baked into the design of new mechanics. There were an astonishing amount of issues revealed during the prerelease process leading up to 1.14 and I was very surprised when the new release arrived when it did as the process felt truncated.

What we need more than anything else is some sort of communication from Mojang on the subject.

@Christopher Martin

I had to up the ram to 4GB for the server to just idle without getting behind on ticks. I saw on the GUI that the ram built up to around 3GB+ almost 4GB before garbage collection was invoked, this obviously happens way quicker when someone is playing. We are 3 players on the server and with 6GB of ram we could play relatively stable, other than the issues I mentioned before. I saw no issue with cpu performance (running on a 2013 iMac) so I don't think the issue is with processing although others have mentioned their CPU running at 100%. My biggest issue was RAM, and I'm guessing there's a very inefficient piece of code somewhere that causes the ram to build up to that point before java vm decides to do cleanup.

The Server Requirements I linked above do say that the server should be able to handle 1 user on 512MB of RAM but in my experience with 1.14, 1.14.1 and 1.14.2 pre release that, that is impossible.

—
UPDATE - The high amount of ram on idle because of garbage collection was my mistake. Setting the Xms Java Virtual Machine constraint to a lower value improved garbage collection drastically when the server is on idle but that makes total sense.

Here's something I'd like to add. I've done some testing on an unofficial Spigot server and done some timings tests there because of a bit better profiler. I completely understand that their unofficial server is indeed unofficial and brings some optimizations like offloading some tasks to different threads or remove some things from ticking. However the reason why I'd like to share results of my tests of running a server on some settings on different Java version with various launch parametres is that when you run some plugins that hook onto events that use the most of the CPU times, they might be able to help the team see what events are causing the issues.
I completely understand that you might want to ignore those results and please if you consider them useless, feel free to ignore them or remove. I personally believe that any kind of result of some testing might be able to help fix these pesky issues that are really not helping 1.14 be the greatest update.

The testing was done on Linux server running a few more servers at once (shared hosting server) running on Core i7 CPU with 5 GB of RAM. The testing included first walking slowly around spawn area, then flying in creative quite a big distance away in one direction then teleporting to another world where I flew quickly from spawn. Then teleporting to another world where a huge amount of player skulls with skins are available for creative building.
Map is force upgraded from previous version 1.13.2 to 1.14 and then force upgraded to 1.14.1.
There are some additional plugins which manipulate with multiple worlds (Multiverse-Core), multiple inventories management plugin (Multiverse-Inventories) while this plugin hooks to Multiverse-Core, plugin for creating NPCs (Citizens 2) while no NPC was created during that time, plugin hooking to multiple events (CraftBook) and protocol-altering plugin that works as a library (ProtocolLib).
From the testing it is visible that only multiworld inventory management plugin Multiverse-Inventories took the most CPU time while travelling between worlds which either could mean that there might be an issue with unloading chunks or loading them.

Timings (every run had set parameters -Xms128M and -Xmx5G):

• Testing on Oracle Java 8u191: https://timings.spigotmc.org/?url=pamozeneya

• Testing on Oracle Java 8u191 ran with parameters -XX:+UseParNewGC and -XX:MaxGCPauseMillis=20: https://timings.spigotmc.org/?url=urojikebuq

• Testing on OpenJ9 OpenJDK 12.0.1: https://timings.spigotmc.org/?url=suvidoxito

• Testing on OpenJ9 OpenJDK 12.0.1 ran with parameters -XX:+UseParNewGC and -XX:MaxGCPauseMillis=20: https://timings.spigotmc.org/?url=olusevoxaj

For comparison (same maps, same methodology, very similar plugins): Testing on Oracle Java 8u191 ran with parameters -XX:+UseParNewGC and -XX:MaxGCPauseMillis=20: https://timings.spigotmc.org/?url=fatohucoqa

Finally again, if you consider these timings results and testing not helpful (because it ran on unofficial modified server even though it is based on original vanilla server) feel free to ingore it or mods delete it. I personally think that every little bit might help solve this very annoying issue.

Definately confirmed for 1.14.1 so far.
Powerful server is simply unplayable even with 10 people on it, frequent crashes, lag spikes, enormous RAM and CPU usage.

Hi all,

I have been experiencing the same issues with a major performance hit in 1.14.x. I created a new world 1.14.2-PR2, Java 1.8.0_74 64-bit on a MacBook Pro (i9-8950HK hexacore, Vega Pro 20 GPU, macOS 10.14.5). Upon creating this survival single player world with no options/flags changed, I moved in the negative x direction solely until I experienced the issue. Upon experiencing the issue, I opened my single player world to LAN w/ cheats enabled so I could access the debug profiler, and ran it for 3 minutes whilst staying completely still and not touching my computer. Afterwards, I also collected a sample of the Java process from macOS' Activity Monitor.

Symptom: After walking for about 1-2 minutes, every 3 seconds, the game freezes for half a second, with a visible TPS and ms lag spike being shown. Please note that the issue continues to occur in Peaceful mode. Please also note that disconnecting and reconnecting makes the spikes stop.

/debug output: https://i.succ.in/2xa8gcHD.txt

Sample of java process: https://i.succ.in/2x653Ohg.txt

Let me know if I can be of help in any other ways.

Edit: Issue persists after /kill @e[type=!minecraft:player]

I realized I could be more useful by isolating more variables in my debug profile. So, I am attaching two debug profiles, of the same world, with me in the same place, doing the same thing (literally nothing-- not touching my computer). One was taken during this bug occurring after walking around the world for a minute, and the other was after I closed and reopened this single-player world (didn't move at all, server performing as expected). Peaceful mode set in both.

Bug occurring (BAD performance): https://i.succ.in/2xm2t9eF.txt

Bug NOT occurring (GOOD performance): https://i.succ.in/2xrioEpF.txt

I hope that seeing how these profiles differ in the same spot in the same world in the same difficulty with the same actions taken during the debug profile process will help in isolating the issue.

@DFRBugger

You say "Please also note that disconnecting and reconnecting makes the spikes stop". Would you say that you were logged out for long enough (more than 15 seconds) for the chunks to unload?

Was this a new world? Were these new chunks? Could any of the lag/delay be attributed to world generation? You do say that you sat still for a long time. 

I am getting the feeling that 1.14 has high overheads, much higher than previous version (don't know if that's intended or not, or whether it's due to bad code or design changes... or both). I suspect in your case any many like yours you're being impacted by this bug and the situation you first encounter load spikes is from world generation. In past versions you might not even have noticed the world generation overhead if your PC was fast enough, but with 1.14 the cost of world generation and the increase overheads of 1.14 might now be exposing you to performance issues you could have had in the past had your PC not been such a beast... and a 8950 is pretty beastly 🙂, even if it is a mobile CPU.

It is very interesting that you have said that performance can return to normal if you exit and re-enter, causing the chunks to be saved out and then reloaded. When I was hunting more details of this issue on our SMP 1.14.2 pre-2 server I found that when it escalated to the point where a crash was inevitable I could avoid the crash by stopping the server, effectively causing the server to save out the chunks and then re-load them on next start.

Perhaps this is some sort of unintended consequence of the new multithreaded file I/O? I hope not... threading is going to be an important part of scaling Minecraft to take advantage of newer CPUs.

I hope Mojang make a post about this soon. The community really needs to hear from them regarding this so we can make informed decisions.

I haven't seen any threads about not being able to break blocks below your feet without them kicking you off or to the side, which is deadly in many common situations in normal gameplay, is this where we're talking about that? Even digging a 2x1 tunnel down for example to install a bubble elevator, or making a pillar to check out the landscape or AFK, or even stacking resources to Fortune, when you break the blocks under you it's almost certain that you will be knocked off of the blocks, and nearly impossible to stay on. If this is the wrong bug thread tell me where to post because it needs attention.

Amber, are you playing on a Spigot server? It happens on ours as well, but not in singleplayer Minecraft

Some info:

For those testing on Spigot, please switch your server back to vanilla before reporting bugs here. I've already found a lot of chunk oversize issues with latest r1 release of Spigot 1.14.1 causing the server to lag as above with  high cpu usage.  When I switched to vanilla, it fixed all the chunks and lag was gone.

second info:

Using a newer generation CPUs Post 2015 did help for my case. If you look at cpubenchmark.net, check your cpu "single" thread rating. It should be at least 1600 points or above. Chunk loading is still single threaded from what I can see, so you need more powerful single thread. But you still need multiple cores so that Minecraft can push other processes like players into the other cores.   This is just from my observation. I've been playing around with a lot of server machines to figure out whats going on. Would be nice if somebody can confirm

Amber - unless you are also seeing your server spew out "Unable to keep up" messages at the same time that you are seeing what you're describing, that sounds like a separate bug, and you should open a new bug for it.

Re: CPU Benchmarks - doesn't really help; the Minecraft-hosting.pro servers are running Xeon E3-1240v2 CPUs which are rated at 2028 on their single thread performance benchmark test, but everything from 1.14 through 1.14.2-pre2 is unplayable even with only a single player on the server, so either the min-spec is significantly higher than that, or there is something more going on.

Mudassar - but if you rent a server it is often impossible to revert server to vanilla if you have already bought a server on Spigot. This is the case for myself as well. I do not have that option. Besides - what's the point of switching to vanilla if all needed plugins will not be able to work... It should be fixed in Spigot or vanilla itself in the next release, as those performance problems and overloads are definately vanilla issues mostly, not Spigot.

I'm also experiencing those problems on my high-end server:

• Blocks reappear after being mined

• Cannot open chests and other containers

• Cannot interact with entities

• "Can't keep up! Is the server overloaded? Running xxxx ms or xxxx ticks behind" all the time

After using /debug I'm getting:

[12:52:36] [Server thread/WARN]: Something's taking too long! 'root' took aprox 118.34182 ms
[12:54:06] [Server thread/WARN]: Something's taking too long! 'root.tick.connection' took aprox 6249.568617 ms
[12:54:06] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 6293.734384 ms
[12:54:06] [Server thread/WARN]: Something's taking too long! 'root' took aprox 6343.352869 ms
[12:54:06] [Server thread/WARN]: Something's taking too long! 'root' took aprox 103.037489 ms
[12:54:08] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular' took aprox 1983.082906 ms

[12:54:25] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld' took aprox 102.850991 ms
[12:54:25] [Server thread/WARN]: Something's taking too long! 'root.tick.levels' took aprox 103.794314 ms
[12:54:25] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 104.203824 ms
[12:54:25] [Server thread/WARN]: Something's taking too long! 'root' took aprox 112.231684 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick.minecraft:pillager.ai.newAi.goalSelector.goalTick.pathfind' took aprox 174.839633 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick.minecraft:pillager.ai.newAi.goalSelector.goalTick' took aprox 175.04956 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick.minecraft:pillager.ai.newAi.goalSelector' took aprox 175.100923 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick.minecraft:pillager.ai.newAi' took aprox 175.148243 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick.minecraft:pillager.ai' took aprox 175.181494 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick.minecraft:pillager' took aprox 175.282578 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular.tick' took aprox 175.316717 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular' took aprox 187.269516 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities' took aprox 188.191736 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick' took aprox 191.603929 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.world minecraft:overworld' took aprox 191.629423 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick.levels' took aprox 192.543432 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 192.897867 ms
[12:54:27] [Server thread/WARN]: Something's taking too long! 'root' took aprox 193.986132 ms
[12:54:31] [Server thread/WARN]: Something's taking too long! 'root' took aprox 119.237488 ms
[12:54:32] [Server thread/WARN]: Something's taking too long! 'root.nextTickWait' took aprox 100.760292 ms
[12:54:32] [Server thread/WARN]: Something's taking too long! 'root' took aprox 130.263373 ms

Although I think all these are just symptoms of terrible lags because of dramatically bad performance of 1.14+ on the server-side.

My powerful server always running perfectly smooth on 1.13.2 - after upgrade to 1.14.1 with a new world generated the server can't keep up even with 10 players and with render distance lowered to 6 (was 15 on 1.13.2):

• enormous resources usage, eating up to 16 GB of RAM in a matter of a couple of hours, even with server limited to 10 slots only;

• CPU also enormously stressed most of the time;

• basically, resources usage is at least about 3 times higher than it was on 1.13.2;

• frequent crashes due to high resources usage, low tps, lags;

• logging in by someone takes very long and is causing terrible lags on the server;

• people are often getting timed-out kicks.

I suppose this is all related to terrible chunks loading and unloading algorithm and also broken AI performance of pillagers / villagers.

Please for tests use vanilla server, the problem its not spigot.

It's not that we don't believe that the problems are caused by vanilla. To debug the game and fix the bug, the devs can only rely on information from the unmodified game, since mods (and third-party software like Spigot) change the source code of Minecraft quite a bit.

Updated client and server to 1.14.2-pre3 as it added more output for chunk loading/unloading, but doesn't look like that is the specific issue that I am seeing here.  Primary culprit still seems to be mob AI based on my profile output results.

Single player connected to server running Xeon E3-1240v2 w/ 4 GB of RAM. Maneuvering around a cave system underneath the border between a mountain and ocean biome. Breaking occasional stone and ore blocks, and encountering the normal set of underground mobs - skeletons, zombies, creepers, bats.

Experience: Much the same as before, block lag with broken blocks re-appearing and then disappearing again a few moments later. Mobs visually moving very slowly or stuttering as they move, occasionally moving very fast if the server frees up enough to catch up to where it is supposed to be.

It is still extremely distressing that this ticket remains unassigned and Mojang devs are remaining silent.

As an experiment, I recreated the world from my previous tests newly in 1.14.2-pre3 (all of the profile results I've attached are from a world that was created in 1.14 and then upgraded through to 1.14.2-pre3) using the same seed to minimize differences.  Created world, allowed the server to stabilize for a moment before logging in, and just proceeded to walk from spawn to where I knew a village was located, near where all of my above testing was done. Almost immediately after connecting, started seeing "Can't keep up" messages in the console, and I can observe some of the same behaviors.  I summoned in some basic tools via creative before changing mode to survival and running the remainder of the test.

Debug profile: 

World seed (if this helps at all): 207227789904888

Just tested against 1.14.2-pre4, and still seeing issues.  Block lag seemed to be a little bit better, but entity lag (villagers, mobs) was still quite bad.  The vast majority of the tick time is still being consumed by mob AI based on the profile results attached here:

This is again with a single player connected to the server; walking around in the overworld on the surface, breaking some random blocks, and killing a couple of hostile mobs. Same duplicated empty world from my previous comment, and same world seed as all of my previous profile result attachments.

(Is this even useful me posting these debug outputs at each updated snapshot and release showing that I am seeing what appears to be the same issue each time? It is feeling kind of pointless at this point given the lack of response.)

There's a similar report for mob-related lag here: https://bugs.mojang.com/browse/MC-151802

And sometimes tickets are being worked on and fixed without any assignee so have faith.

I have really big issues as well with a vanilla minecraft server on 1.14.1. Performance is really poor. 

I updated my server to 1.14.2 and it has lasted 50 minutes without crashing

No noticeable improvement with the full release of 1.14.2.  Still seeing huge amounts of block and entity lag with just a single player connected to the server.  Looking at the debug capture, AI is still the number one culprit.

To be fair, there were no notes about fixes to this in the release notes, but tested it for completeness anyway. Not sure if it would be worth including the actual console log here as well since it does give some more specific examples that get rolled up into the debug profile output.  One example that stands out just browsing back through the console output:
 
[17:20:50] [Server thread/WARN]: Something's taking too long! 'root.tick.levels.mcu-dupe minecraft:overworld.tick.entities.regular.tick.minecraft:spider.ai.newAi.goalSelector.goalUpdate' took aprox 112.972352 ms
 
So that one specific behavior took over twice as long as a single full tick should take. Due to these issues, I've already canceled my server hosting plan, and my small group has basically disbanded because it became impossible to maintain with this level of performance. I do hope the problems get fixed eventually because it would be fun to play and/or run a MP server again in the future.

I can confirm, my servers run even much worse on 1.14.2 than 1.14.1 as described: MC-153239

I also feel as though 1.14.2 also made things worse on the server side. 1.14.X was already slow, now with this new light calculation the game is pretty much unplayable. I really wish we could get some sort of acknowledgement from the devs regarding the server side performance. Clearly it’s not a small issue if it’s being talked about on the forums, the tracker, and reddit. The #1 concern should be this at the moment. On my server we have 5 people max. 4GB of Ram dedicated and TPS if often <17. Eating food is slow, drawing a bow is impossible, and fighting against any mobs is ridiculous. It’s concerning that this glaring issue seems to be continually looked over and never spoken about in the blog posts. They claim they’re going after the more “critical” issues and with 1.14.3 it sounds like everything is more minor. It’s almost like the game isn’t play tested in multiplayer or something.

Issue seems worse going from 1.14.2 pre 3 to 1.14.2. Server TPS went from a average of 18-20 in 1.14.2 pre3 down to 15-17. I really wish there was some sort of response from Mojang about this. Our server population went from a steady 10-15 players down to maybe 3 on at a time since 1.14

If the next update is composed of "a bunch of less critical bugfixes" I fear my nearly 2 year old server will be dead. 😞

Try the latest Spigot build - I can confirm that 1.14.2 on latest Spigot from today became playable now and as "good" as 1.14.1 !

@nick killeen

I agree, 1.14 has obviously not been sufficiently tested on servers. 

There have been sweeping changes made behind the scenes without any community consultation. Built your massive farm just outside of the what would have been the spawn radius in 1.13 and before? Nope, spawn junks are much, much larger in 1.14 (and there has been no explanation for why). And there is a massive area around spawn that can lazy load and stay loaded for ever, even if everyone logs out. The only way to unload it is to reboot the server. Don't run a perma-loader for your spawn chunks? Doesn't matter, with the new spawn mechanics the spawn chunks will stay loaded, no matter what dimension your players are in. Hell, it'll probably stay loaded without any players logged into the server at all, even if that's the last freaking thing you wanted!

These changes could at least partially explain some (but by no means all) of the extra lag. It certainly explains why memory requirements for servers have grown by a factor of two or three.

I'm used to Minecraft Java being unloved and under-supported, but it's hard not to feel that this update was coded by inexperienced people, with little or no background in Minecraft (and certainly no server experience) and with no guidance or support from management or other people inside Mojang with more Minecraft Java history.

Not sure there is enough evidence to justify that feeling? Watch this video, it is VERY eye-opening. MethodZz has numerous videos on 1.14's insanity, but this one captures the essence of the issue very well.

https://youtu.be/kVlDtWRoWuA

I am starting to wonder if Mojang's plan to incentivise people to move to Bedrock is to just render the Java edition unplayable.

@kamil piglowski

I am not sure if this is the right forum for discussing Spigot as this is the official Mojang forum and Spigot is a 3rd party server that emulates most of the base mechanics, but differs in some specific ways that make it totally unsuitable to a segment of the playing community.

@unknown

The resolution for MC-141484 may be what your issue is.

I have run a couple debugs now, all showing tickrate slowing down and often taking more than 100ms with just a single player. Meanwhile cpu spikes of 20-40% and 4 times the idle usage compared to 1.7 versions. Tried multiple java versions along with zulu and official oracle binaries, tried vanilla, Spigot and even ran builds from other systems in case something was wrong there. Started experiencing lag and unresponsive behavior in singleplayer now too. This is not acceptable! 1.14.2 as of this post is not in any playable state. I frankly don't know what has happened, but since 2 major versions this has only gotten worse.

I can see why the thought comes to mind that "someone" is trying to kill the java version, even if unintentional, it is working. If it wasn't for the fact Win10 was such a disastrous POS as well. Mojang, with all due respect, fix the product I paid for!

My server is Xeon 4-cores, 16 GB RAM, SSD HDD. This is one of the most high-end hosting plans on the market.
Back to 1.13.2 I could handle 30+ players with 15 render distance with constant 20 TPS and zero lags. 16x16 = 256 chunks per player x 30 players = 7680 chunks active.
Currently on 1.14.2 same server can't keep up with 10+ players with 6 render distance and often drops TPS to as low as 11-12 with huge lags. Restarts are needed even every couple of hours.
Once again, with only 10 players and render distance as low as 6. 7x7 = 49 chunks per player x 10 players = 490 chunks active.
How is this possible that the same powerful server is running on 1.14.2 much worse, with 15 times lower chunk load than it was on 1.13.2?
We don't need any your new lighting engine or new AI of mobs or whatever else that makes the game 15x more demanding and simply unplayable.
If you can't optimize it or even test it before releasing to the market just please don't do it... don't ruin that great game you've made.
Please fix broken chunk loading algorithm or this terrible overloading AI of mobs or whatever else and make the game playable.
Or maybe rollback to the previous mechanics from 1.13.2 and just let current 1.14+ worlds work on them.

^{8.08 ticks per second on single player after updating to 1.14.2, my god this is horrendous.}  

Just want to add a comment to confirm that I have had to downgrade my server back to 1.13, as 1.14 is utterly unplayable. Everything in this thread is exactly what has happened to me. Hoping to get a fix, my friends and I want to play 1.14.2 soon

If you want it playable, have a look at your CPU model through CPU Benchmark.

FIRST: Single Thread: https://www.cpubenchmark.net/singleThread.html  
MINIMUM Benchmark Points should be: 1600 or above (This will help prevent some of the TPS/Ticks falling behind problems in certain cases, such as during chunk loading and pvping but its not 100% perfect, loading chucks too fast will overwhelm like with any version of Minecraft. Though 1.14 series does use more CPU for this) 

SECONDLY: For this type of CPU, you should have at least 4 cores reserved per Minecraft instance. So if your running 4 instances of Minecraft 1.14 servers, 16 cores is recommended. You should also have extra cores reserved for OS and other applications you might be running.

@unknown
 
Can you please stop repeating this? Even if you throw hardware at the server that does not resolve the UNDERLYING issue. You're just telling people to spend money upgrading to work around Mojang's error.

Yes, there is a floor to the CPU performance that can run a Minecraft server. This issue is about how quickly that floor has raised and whether or not that speed of that rise is legitimate or not. There has been an almost order of magnitude increase in per-user server load and it is unfair to ask people to lay out cash to work around a problem that Mojang SHOULD BE FIXING.
 
There are clear indications of MASSIVE inefficiencies in 1.14 and a significant lack of optimisation, both client side and server side. I suspect that this issue is because of a couple of big ticket items, like the insane increase in spawn chunk radius and 1.14's tendency to keep many many MANY more chunks loaded than previous versions and the INSANE increase in Villager processing cost, and a bunch of small ticket items are coming together to create the issues that people are experiencing.
 
Time and again people make it clear they are comparing 1.14 to 1.13 and you keep acting like they don't know what they are talking about and just should upgrade. Stop it. There is an obvious issue with 1.14, people keep providing mountains of evidence of the issue and you keep repeating the same non-advice. THERE IS NO AMOUNT OF HARDWARE YOU CAN THROW AT 1.14 TO MAKE IT RUN CORRECTLY: no matter what hardware you buy Minecraft will still not run efficiently. Yes, you can make it smooth, but the hardware required to do so (on a per-user basis) is 4 or 6 times 1.13. THAT IS INSANE. There is not enough extra content in 1.14 to justify that. There is an obvious issue. It is clear as day.
 
 

Christopher,  

I didn't realize i mentioned upgrading of hardware before sorry. I saw a lot of crying posters so i was just making a post out to them.

Ive been playing around with so much hardware past few weeks since the release of 1.14 just to try making it work. This same issue happened when 1.13 was released.  Mojang never fixed it.  I don't see them fixing 1.14 either.

So solution, hopefully a temp solution (keep dreaming), is to upgrade,  and yes maybe waste a lot of energy in doing do, which may impact the world environmentally. But since I did the upgrades ive had very little problems. 

 Peace

@Mudassar Khan

You show a complete disregard of this issue. I have modded 1.7.10 servers running on the very same hardware, generating chunks like crazy without seeing such severe and consistent issues. Since 1.12 1.13 the server and singleplayer performance has gone down massively. Constant and I mean constant high tick timings and server crashes from ticks taking 10 seconds or more. In contrary 1.7.10, with mods, more players and built worlds run better and more consistently with less tick time.

I am just guessing, but some "improvement" meant to increase multithreading just causes lots of dead threads that slow down finishing up ticks resulting in them consistently taking longer. These issues have since 1.14 penetrated into singleplayer, heck I keep hearing about issues outside of our servers daily. The fact these issues are being entirely ignored by Mojang is infuriating so many people now. The handling of bugs and priority given to things that are trivial to near impossible to reproduce is killing the game. We now have sluggish servers consuming 4 times the resources, singleplayer worlds that won't allow for proper combat against mobs and blocks that lack interface or clear purpose as of yet. This update has had one of the most rocky starts in the history of the game. We have had this before, but eventually things stabilized. Since Bedrock and M$ came along the quality has declined and the updates have gone back to levels of 1.3.2, if you remember that mess.

It frankly is not acceptable how the game runs and throwing hardware at the problem is not a solution, long or short term, if we did this for everything there would be no innovation or optimization. Given how widespread the issue is becoming and how obvious it is once you start digging just a little bit I wonder if you actually spent some time running profiling or comparing versions in a controlled environment. Only because you are unable to reproduce a problem or have somehow found a way to ignore it does not mean it does not exist and it much less means that it does not need investigation and attention, especially given how many have reported this and continue to report it for literally every version that is released.

Please note that the comment section here on the bug tracker is not meant for longer discussions. Every time someone posts a comment here, it gets sent to 90+ users via email. Please only comment if you found out something new about this issue (for instance, if it happens in a version that is not yet marked as "affected" in the list on top of this page).

You can use the /r/Mojira subreddit if you want to discuss this issue. Someone created a post about this ticket there already: Link. Please divert all further discussion to there.

Recently after many days of observations I discovered - and now I'm 100% positive about it - that one of major impacts of server-side performance is also AI of pillagers and patrols. My server keeps stable 20 TPS but when I meet a patrol TPS starts to drop and after wiping out the patrol it is raising again back to 20. I think this is something very critical that devs should look into.

Where the issue originated for me: (I originally posted this in https://bugs.mojang.com/browse/MC-151532 but figured it may be relevant) (I am on singleplayer)

I am unable to eat food.  Even by right clicking the food, my hunger bar and the food count don't change.  See the vimeo video:

https://vimeo.com/335597417 (26 mb > 10 mb)

This world was originally made on 1.12.2 I believe, but I have opened and upgraded it in each of the minecraft versions leading up to this one, and never faced this problem in 1.13.2 or any other version.

This has happened to me on multiple occasions on 1.14.  It happened to me twice after I tried to drink a potion that was made in 1.13, causing my world to lag out/crash, and I had to remake my world from backups.  This is the first time this issue has happened without me trying to drink an old potion.  I noticed that leading up to this, when I tried to eat there would be a ~1 second delay between me finishing eating and my hunger bar changing, but now I just cannot eat at all.

 

Things I did leading up to this that I normally don't do:

*

Saved and exited, and reloaded the world multiple times.  This was in an effort to get more hostile mobs to spawn (https://bugs.mojang.com/browse/MC-147890) .  After coming back, there were a lot more hostile mobs, multiple wandering traders (which you can see in the video), a lot more lag than normal, and the 1 second delay between me finishing eating and my hunger bar changing occurred.

Changed my video settings; max framerate from unlimited to 120 fps, clouds from fancy to fast; entity shadows to off; particles from all to decreased; smooth lighting from max to min 

Gave above average priority to the javaw.exe process

To address the hostile mob point further, I noticed that on 1.14 right from the bat that very few mobs spawned.  I remade my world twice from backups as mentioned, and for both of the remakes I never saw any pillagers despite playing >10 minecraft days on each remake.  So the two factors that really preceded all the haywire low-tick issues are 1) eating old potions and 2) saving/exiting and reloading multiple times, causing a ton of mobs to appear.  I'm not sure if the low tick issue was present before those events, but besides the mobs issue everything seemed normal.  

Now whenever I load minecraft (including updating to a new patch) it just starts out with terribly low ticks per second.  Villager movements look like they lag a lot (the walking animation is not smooth).  

I have a feeling it is something to do with entities spawning/ despawning at least that's how it feels, we are seeing the CPU usage go through the roof after stable play. If we are to simply restart the server it does as it should and restarts but immediately starts and holds the same high CPU usage, you have to fully stop the server wait a few minutes and then start to see the CPU return to normal this was never the case in 1.13.2

The reason I say about mob spawning, in particular, is once we've started to see the CPU creep up I have changed over to spectator mode and the number of mobs in caves which should have despawned is unbelievable.

It is unclear if the mob despawning issue shown in this video was ever fixed from the initial 1.14 release, and lines up with what some folks have described above:

https://youtu.be/kVlDtWRoWuA

TL;DR - chunks are not unloading correctly based on render and server render distance, and mobs are not despawning correctly when moving the appropriate distance away from them. The video outlines in detail the specifics of what was seen.

I don't believe that is the only issue at play here, based on the numerous debug logs I have provided showing AI taking abnormal amounts of time without a corresponding spoke in CPU usage. (From a programming perspective, that sounds like a livelock / wait loop that isn't being gated out of correctly, but I'm not Gnembon and don't have the tools to deobfuscate the source code to do more detailed debugging.)

Dual Intel(R) Xeon(R) CPU E7520 @ 1.87GHz
4GB of RAM
2GB of swap
Ubuntu 16.04.6

java version "1.8.0_201"
Java(TM) SE Runtime Environment (build 1.8.0_201-b09)
Java HotSpot(TM) 64-Bit Server VM (build 25.201-b09, mixed mode)

java -server -Xms512M -Xmx4096M -XX:+UseG1GC -XX:+CMSIncrementalPacing -XX:+AggressiveOpts -jar /opt/msm/servers/Dorkville/server.jar nogui

KiB Mem : 4046312 total, 2816240 free, 984832 used, 245240 buff/cache
KiB Swap: 2096124 total, 2096124 free, 0 used. 2804164 avail Mem

I've read this thread and I do not see a resolution so I'm adding some of my crashplan logs and my latest log with /debug start enabled

On an idle server with no one logged in with /debug start my logs quickly fill up with

{{[20:51:59] [Server thread/WARN]: Something's taking too long! 'root.tick.levels' took aprox 117.042054 ms
[20:51:59] [Server thread/WARN]: Something's taking too long! 'root.tick' took aprox 117.640817 ms
[20:51:59] [Server thread/WARN]: Something's taking too long! 'root' took aprox 118.758035 ms}}

"Adjusting" the hardware has no effect on the frequency of the crashes.

• RAM up to 64GB

• 4 CPUs

• Various different java options

My previous ticket was closed with a link to this ticket and the the closing message was, "This is caused by severe server lag".

I am playing on a Gigabit Ethernet link with the server on a 10GB link. I do not think the problem is "network lag".

You can see the server doesn't use any swap and there over 2G of RAM free and the CPU is around 1.2 load average. I do not think the server is working hard or over loaded.

Are there option or things I can to to help debug this problem?

Changed to java's options?

Thank you for your time.

@Bob Tanner - you should also attach the debug profile file from the debug folder that is generated from running the debug start/stop commands. 

Also "server lag" does not necessarily mean network lag - in this case they're referring to the Minecraft server (the application) lagging due to whatever this bug, or set of bugs, is. You're not going to be able to work around this with adjustments to your JVM arguments, because this is something buggy within the Minecraft server code itself, so we are at Mojang's mercy here.

Discussion for all reports on Mojira related to Performance Errors.

You are tried to just update the server jar file to 1.14(or newer), but your saved world file was kept as it is.

My server also has the same symptom which was lagging extremely, when I updated the jar file from 1.13.2 to 1.14.2 directly.

I found that if any player moves nearby a chunk which is old (not generated by 1.14.2 server), the server lags as all of the players' movement 'undo' and the server's console shows 'Player XXXXX moved too quickly'. Once the server loaded all of the old chunks that are near enough to any player, the server didn't lag anymore.

Due to these, I guess that the server was trying to upgrade the old chunk data to the newest version, and the conversion is very slow, so the server lags. When the conversion has been done, the server runs smoothly.

I also changed my server running script to let it restarts every 3 hours. After the restart, the server runs extremely smoothly a while.

You might want to try to upgrade all of the saved world files to newest by using the client's upgrade world option.

On the wiki it states for the new pre

Performance

• Improved performance.

I can confirm that that is a lie. Just tested, still the same performance outside some margin of error.

Dude, "Improved performance" can mean many things. For one, performance can also mean client-side performance (read: FPS). And "Improved" does not mean "It is the best it can possibly be now". Accusing Mojang of lying is way over the top here. You can tell by this report still being open that they didn't even claim that server performance is completely fixed.

@violine1101
Do you have any info is there a chance Mojang will fix dramatic server-side performance issues in final 1.14.3 release?
Do you have any info are the devs aware of this issue and at least working on it?
Your answer would be much appreciated.

I know that they're aware of this issue and are actively working on it. However, this ticket here describes multiple different issues that all have the exact same symptoms, so as you can see, fixing this issue takes quite a while. Hence it's impossible to say in which version the issue will be fixed for good.

The problem is, seeing a ton of trivial bugs fixed on each pre which gives the impression that not everyone is working on solving an issue that has made the game pretty much unplayable and that feels very much like a slap in the face.

This is not just about server performance seeing as tested in this case means firing up a singleplayer world and running the profiler there seeing the same results as before almost to the millisecond. Fresh world, fresh installed, even rebooted before doing it to clear memory. Have done the same exact test for each time a new snapshot or pre has come out, all the way back to 1.13. the results are not improving and I have indicated that on both this and the other issue about the performance. Many have followed to do the same, yet the lack of official statement is what gets so many riled up about this. All this testing, data and confirmation a problem exists. The fact they are aware of it is nice, but an official "We know, here is what we will try to fix it" would be nice. I know very well how boilerplate that part is and that it could mean anything, but performance has only deteriorated over time, hence this and other reports, so even the slightest hint toward increased performance while not specifying what that is and still getting the same profiling results feels like a slap in the face to me, sorry for being so human.

I'm sorry for making such a wind, sure, it is not nice, but someone has to be this blunt. I setup a modded server, 50 or so mods, on 1.12.2. Both it and the totally vanilla server are now there idling, no players, only the spawn area being chunkloaded. Guess which one is consuming more cpu time... It's painful, honestly just painful to play the game this way. Even in singleplayer being teleported back due to tick timeouts, dying because of that, killing your favorite pet because the game thought it was in the way. It is becoming an unplayable state no matter single or multiplayer.

I do hope that we will eventually get some form of official statement as to even a hint at what they think may be wrong and what is being attempted to fix it, because as it stands Minecraft Java Edition is not in a playable/enjoyable state.

This is not a discussion forum. Please do not comment if you do not have further information to add, since it makes it harder for us to find relevant information to fixing bugs.

We are aware of this. Other bugs being fixed does not mean this isn't being worked on.

Thank you @slicedlime

Something is wrong with some villagers pathfinding a bed during nights. Probably looping and causing tps drops.
We had big tps drops during nights and when we destroyed all beds close to villager farms TPS started to behave much better.

Currently, in our opinion (we run two powerful dedicated servers on 1.14.2) the biggest problem causing huge lags and enormous server tps drops are:

• far exploration, especially using elytra or boats (flying elytra by just 1 player can drop TPS below 10 very fast and make the server unplayable);

• meeting pillager patrols (something is wrong with their AI, sometimes making even single patrol to start dropping server TPS);

• initiating raids of pillagers (raids are sometimes causing huge TPS drops);

• creating villager farms (it seems their AI is bugged and some villagers can drop server TPS);

• going frequently through Nether and End portals (causing lag everytime going through portals).

And this is all with only 12 people on the server and render distance as low as 6.

In comparison - same server could easily handle 30 people and render distance 15 back to 1.13.2 without ANY lags and with constant 20 TPS.

I'm talking about 1.14.2 version server.
Not sure if it is any better at 1.14.3 pre-1.

I'm probably doing something wrong, but when I type in "/debug start" it tells me it's an unknown command. What am I doing wrong?

You need to have cheats enabled (singleplayer) or be a server operator (multiplayer) in order for the command to work.

I discovered that when I left my village island, there did not seem to be any tick problems.  This included going into the nether, and going to different bases to fight monsters, which spawned at rates similar to 1.13.2.  Debug results below:

My game only has the low tick problem when I'm around my village island, so I'm almost certain it's a village/pillager thing.

@Justin
I can definately confirm this after my observations from today.
On my other server, with most of the world generated on 1.13.2 and then updated to 1.14.2 performance is quite ok. Not as good as 1.13.2 and there are stille some lags but it's a huge difference comparing to my server with pure 1.14 world. There are still some lags but not so big and the server runs pretty smooth. When I explored far away on this server and started to generate NEW chunks on 1.14 chunk loading and generating was of course much worse that in 1.13.2 but acceptable. TPS was still stable 20.
HOWEVER, when I discovered the first village generated in 1.14 server TPS started to drop drastically introducing huge lags with all symptoms in this thread and server eventually crashed...
Something is clearly wrong about villages and villagers behaving in 1.14. Villages and villagers in 1.14.2 are major gamebrakers and server killers, much worse issue than just chunk rendering itself.

Villager TPS is a whole issue by itself: MC-152630 and MC-151150.

This is definitely still an issue. My server is running with plenty of resources and ran perfectly smooth on 1.13.2 but as soon as we made the transition with an upgraded world to 1.14.2 we've noticed huge lag issues server wide with every action including chunk loads, entities, and more. I've checked this on bleeding edge SpigotMC and Vanilla build and nothing seems to be changing.

Why is this issue being ignored? 

@Matt that's a mighty fine question, this is becoming a growing problem for me on my server and I'm sure it applies to others.

Just ran a debug and I'm getting the same message listed previously while there are 1 player and no players online with latest spigotmc with specs 12 GB RAM, 4vcores cpu. The following showed up repeatedly while doing nothing:

-  Something's taking too long! 'root.tick.levels' took aprox 121.536258 ms

- Something's taking too long! 'root.tick' took aprox 122.517502 ms

- Something's taking too long! 'root' took aprox 115.863161 ms

- Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick.entities.regular' took aprox 101.537296 ms

- Something's taking too long! 'root.tick.levels.world minecraft:overworld.tick' took aprox 107.894572 ms

+ more. This looks like it has something to do with the rampant lagging on the version, but regardless this issue needs more attention. It's making the game next to unplayable for many servers. If this is fixed in the newest pre-releases then a mod should mark this as resolved but as far as I know it hasn't been fixed.

@unknown, to answer your question:

We are aware of this. Other bugs being fixed does not mean this isn't being worked on.

– @unknown in this comment from 12 days ago

I also can confirm this I run my Minecraft server with 28GB of ram dedicated to it and have extremely bad lagg in raids and 1.14 chunks even with only 1-2 people on hitting about 8-4 tps however if I teleport back to old 1.7 generated chunks the tps goes back to 20.
Processor: Intel Xeon-E 2136 - 6 c / 12 t - 3.3 GHz / 4.5 GHz
Memory: 32GB
Two NVMe PCI SSDs in Raid 0

This server is running Paper version git-Paper-51 (MC: 1.14.2) (Implementing API version 1.14.2-R0.1-SNAPSHOT)

this has been happing when I am flying around and loading in chunks. this causes chunks to take a while to load. also, it is in 1.14.3 pre-release 4.

1.14.3 has not fixed the issue for me; if anything, it has made it worse...

Generally, after update to 1.14.3, first hour on my two servers seem to be fine and working better comparing to 1.14.2, especially chunks loading.
But we can really see about that after at least couple of days, to be sure if 1.14.3 is working better than 1.14.2.

I forgot to mention - this is with raids and elytra disabled at the moment.

UPDATE: with 2 people exploring the overworld and generating new chunks, one of them on horseback and second one with speed potion, server TPS dopped to as low as 10, creating huge lags and making the server unplayable (restart needed). Chunks generating in 1.14.3 seem to be better than in 1.14.2 but is still way too slow comparing to 1.13.2. Couple of players exploring or only one with elytra is still overkill, even to dedicated high-end server like mine (Xeon 4-cores and 16 GB RAM).

1.14.3 has seriously improved this issue, but it still an issue.

1.14.3 works better than 1.14.2 with this issue, but I have to say some things. This issue affects Single Player Mode too with exactly same symptoms. And currently these lag spikes almost killed me more than one time or even killed. Some examples:

Mining to find my stronghold, I've mined 4 blocks, move to their position, and these blocks wasn't deleted so game decided no render them but apply suffucotation damage to me. I could save my life mining beside blocks and move to them.

In nether fighting Blazes at their spawner... sometimes they just stop doing stuff and I can't hit them while they are stopped.

Doing a Pillager Outpost I've died (it's my fault don't heal before), but I couldn't block an arrow because entities stoped just when I tried to hit them, then put shield up... but when entities recover their behavior, game considered that I had to receive one more arrow to kill me and process my damage too.

Attached are two profile results where there were issues with chunk loading (2/7/2019). I am using a copy of my main game world with commands specifically enabled so I can capture debug profiles. I have confined my testing to the Nether hub in my world where I have constructed tunnels in the Nether ceiling aligned to the four coordinate axes. These tunnels have a length of 75 chunks (north), 105 chunks (east), 88 chunks (south) and 230 chunks (west). My testing consists of running along the lengths of these tunnels until the chunks stop rendering. This typically happens after 5 to 10 minutes and often requires me to turn at some point (eg: turn around at the end of a tunnel or make a right-angled turn at an intersection).

When the issue is occurring for me, chunks stop loading and the missing chunks cannot be interacted with. Blocks in the missing chunks have no hitboxes and the "looking at" information does not appear. After waiting for a few minutes (typically 3 minutes) the chunks will usually appear. It is possible to fall out of the game world by entering these missing chunks.

Some interesting observations:

• I have had the missing chunks suddenly appear after pressing F5 to change the camera. (My usual F5 camera settings is first-person view.) This has happened a couple of times, but usually after waiting for at least a minute. I discovered this accidentally. The attached traces include occurrences of this.

• I have had the chunks suddenly stop loading after pressing F5. This happened once.

• On more than one occasion, I have had cave noises (ambience) play immediately after the missing chunks appear. This has often been Cave 1 ("train horn").

I suspect there's a desync between client and server regarding the position of the player with respect to chunk loading.

I have recently improved the performance of the game world by removing a village (by relocating the villagers and iron golems) and all aquarium fish (fish spawned from buckets) from my spawn chunks. However, the chunk loading issue still persists.

Before posting any further comment, please note the following points:

:info: Only comments related to the very latest version of Minecraft are relevant, this is currently 1.14.4 pre-release 1. Please refrain from posting any further comment if you are not using the latest version.

❌ Do not comment on what you are experiencing in game (block lag, rollbacks, can't eat, won't load, can't move, can't open, can't chat, etc). Those are only consequences of the lag but won't help knowing the cause and fix the issue. We are not interested about knowing those.

:info: In order to diagnose your issue, we need  to have the following files which you have to generate in game and attach to this ticket:

✔ Please systematically run a debug profiling when you are experiencing lag, see the panel's notice in the ticket's description to know how to proceed

✔ Please systematically run a debug report when you are experiencing lag, see the panel's notice in the ticket's description to know how to proceed.

✔ Link to your comment to both your debug profiling and your debug report by using the Attachment (paperclip icon) button in your the comment's text editor.

❌ We do not take reports coming from modded game versions nor modified server programs (no ❌ Spigot, ❌ Paper, ❌ Forge,…), only ✔ Vanilla

❌ Do not comment if you don't have a debug profiling to post (/debug start - stop)

❌ Do not comment if you don't have a zip file containing a debug report of your world (/debug report)

Use the following template to comment any further:

• Game version:

• Debug profiling: "link to"

• Debug report: "link to"

Game version: 1.14.4 pre-release 1

Debug profiling:

Debug report:

Sequence: chunk loading lag seen, /debug start, chunks loaded after about a minute, /debug stop, /debug report.

Debug profiling:

Debug report:

Sequence: chunk loading lag seen, /debug start, /debug report, /debug stop, saved game (chunks not loaded).
Screenshot: (chunk loading lag)

@unknown Server does not look overloaded, runs at 20tps with lots of idle time, so it looks more like chunk delivery/rendering issue. Can you show your F3 screen?

To get an F3 screen, I will need to run the test again. It will take a while. I will post again when this is completed (though it's after 11 pm here so I will need to stay up late for this). I will do the report while chunks are not loaded as per the second profiling.
I found something interesting in the second profile. In that profile, check the loaded chunks for the Nether against the player position in "entities". The chunks are centred at about -183,0 (chunk coords) but the player is in -171,0 (the banners in the screenshot would display the number "171" if they were showing.)

Hmm, that's actually good observation - spawning area is misaligned from area marked with player tickets. Thank you for info, no F3 needed. Though this is probably separate issue, since it has nothing to do with lag (there is probably one for chunk loading EDIT: it's MC-151082).

This isusue only apears when chunks unloading or saving etc aka when player moving.  When it stands still the isusues doesnt exist. Chunk loading doesnt affect this.
This is what was done during debug.
https://youtu.be/PFKItvYVnl4

I'm glad I'm not the only one who is experiencing this.

I haven't properly played singleplayer for a good hour or less because of this particular issue deterring me from enjoying the new features that 1.14 has to offer. Block lag, entities are incredibly slow, the day-night cycle constantly jumps, etc. I never had this issue until 1.14.X got released, and I suspect this is affecting many multiplayer servers too.

I'm not tech savvy, but if all looks wrong, I can easily notice it. The image above is my F3 interface and I wonder if any of the info there confirms what's been troubling my experience. Thought I would leave my two cents on this, and with all due respect Mojang, please fix the product what I deem as my personal therapy. I paid good money for this.