Mob spawning rate in the Overworld is reduced

Having the same Issue after upgrading from 1.14.2 to 1.14.3
The Guardian farm i was working on in 1.14.2 was dangerous to be in the water. After 2 days of playing on 1.14.3 i have seen maybe 4 Guardians total, no hostile spawns at nights, even on unlit nearby islands. Only mob i have seen spawn in are Phantoms after going days without sleeping. Will look in to this more when i get a chance tomorrow and see if i can narrow it down any.

Noticed same problem. Looks like mobs are spawning underground only

Same problem after converting a 1.14.2 world to 1.14.3, monsters don't seem to spawn at all, neither do friendly creatures. They only spawn underground it seems. Monsters spawn fine when using spawn eggs.

Update:
Ok so i have done a little more testing using the commands and it appears that hostile mobs are not despawning at 128+ blocks again in 1.14.3 as they should again, similar to what was in MC-147890
Standing 4000 blocks away from world spawn I can execute a data get command and pull the POS of these mobs which shows them being in spawn chunks and not despawning after I left the area.
Which I assume is why there are little to no hostile mobs spawning around the location I currently am.

same problem, few mobs underground and barely any on surface.

Since updating my server from 1.14.2 to 1.14.3, the only spawns I get are the following :

• Phantoms as previously said by another user--

• Illager patrols

• Zombies from Zombie siege

• Illagers from Raids

• Mobs spawned via Spawner

I'm 90% sure that "standard natural spawns" do not happen since I got a big slime farm and it does not produce anything anymore.

For 1.14.4 pre-release users: please attach result of `/debug report` command.

@Bartosz Bok 1.14.4?

^ On 1.14.4 pre-releases. See notice panel on how to proceed.

I found a workaround (mobs started spawing anew) by installing "paper spigot" still don't know what went wrong.

1.14.4 Pre Release 4?

In previous 1.14.x release mobs could aggregate in non-ticking chunks (due to MC-151772). For example, here's how distribution of entities looks like in attached report:

Unfortunately, those mobs need to be killed before normal spawning can be restored.

Please note that using '/kill' command will not remove those entities until player gets close enough to chunk to tick.

So you want to say that this bug is leftover from another fixed bug and is prevented from happening again, but also you can't fix already affected worlds. Those affected worlds can be fixed manually by making trips around player bases (mobs on ticking chunks will despawn naturally).

Imho you can fix this bug by forcing all chunks to tick all mobs one tick making those possible to despawn, while updating world from 1.14.1-1.14.3 to 1.14.4. This can break mobswitchers based on despawnable mobs sitting in lazy chunks though. On the other hand in modern mobswitchers there are named or non-despawnable mobs like witchers or shulkers, those won't be affected.

 I guess on singleplayer setting render range to max and then slowly walking away is option for despawning hostiles. Though it won't do anything with bats.

so we’re just gonna leave this bug unresolved?

I'd suggest resolving this by killing/despawning forcifully mobs that would despawn normally on loaded chunks while updating chunks to 1.14.4+ from 1.14.0 -1.14.3

This bug can occur also on servers and be visible only when certain people will be online. This will be hard to fix manually by players/server admins.

This bug can also affect players that don't know it affects them (lowering significantly spawn rate, but not fully disabling it).

With this in mind I ask you to fix this bug in described way.

Having the same problem here, running 1.14.3. I've built a witch farm in a 13x13 chunk "hole" and I'm playing with a render distance of 8 so no mobs can spawn outside of the perimeter. Also the guardian farm was working relatively well and now if it spawns 4/5 guardians per minute is too good. I've also tried 1.14.4-pre6 and the behavior is the same. 

Hi, i check if my world, updating at the new release (1.14.4) from 1.14.2 keep spawning mob but, once updated the mob keep not spawning (excluded the mob spawn, pillager, ecc..), but if i downgrade the world at the previous release the mob spawn normally… How can i solve?

Update after two hours of some test:
I tried to despawn as many mob possible (gamemode creative -> peaceful -> tp in the position of mob find in the debug report) after several minutes of cleaning i test if the mob spawn normally and it's work, but i don't know if this definitely resolve the problem or if it will only be temporary

I still have this issue with 1.14.4. No hostile mobs spawn at all.

I still have this issue as well.

3 debug report posted (location in zip name).

I start having the same problem after updating from 14.1 to 14.4.

Hostile mobs simply don't spawn in overworld.

After speaking with one of the operators on a server I play on that recently got upgraded from 1.14.2 (world generated and played only in this version) directly to 1.14.4 (probably with no upgrade commands run?), I believe we too are experiencing this issue.

I've asked the operators of the server to please look at this ticket and implicitly to provide the /debug report and other information as requested.

We confirm that there are practically no mobs respawning in locations such as ocean monuments/temples, and that there are disturbingly few natural spawns in untouched caves.  (The operator was able to use spectator mode at spawn where I'd been waiting for a bit to see if there were too many mobs there.)

I updated from 1.14.2 to 1.14.4. I reduced the render distance to experiment with my Zombie Pigman farm. After changing back to a render distance of 8, I noticed hardly any spawns in the Overworld. I finally solved the problem by resetting the render distance. No particular distance, it just needed to be reset.

I am having this problem on my private Minecraft server, where I play with 3 others.

It's especially noticeable at my slime farm which I built and where not even one slime had spawned after roughly two hours of AFKing (I actually got one single slime spawning in this chunk before I built the slime farm by /killing all zombies, skeletons, pillagers (291!) and creepers, so I know, that it's an actual slime chunk).

But also on the surface I get quite low spawn rates while on difficulty hard.

There is a separate issue with slime spawning: MC-153326. Perhaps that is relevant for you.

@violine1101 I think, that's not the whole issue, maybe it's both, because as I said, the spawn rate of basically all hostile mobs is pretty low.

for me this is not only in the overworld but in the nether too, not sure about the end, i don't think the problem is there, but definitely in overworld and nether

One of the servers i play on, it seemed overworld and end dimensions are fine with spawning, but not in the nether for some reason.