[MC-137537] Walking into a different chunk causes lag

The bug

When walking into a new chunk, Minecraft lags for a single frame.
Video: https://streamable.com/z8c88

How to reproduce

Create a new empty world
F3 + G to view chunk boundaries
Walk into a new chunk
→ ❌ Notice brief fps drops

Linked issues

is duplicated by 12

MC-137540 Stutter Lag Resolved

MC-137665 Significant lagspices while moving between chunks Resolved

MC-137674 Small freezes during the generation of new chunks Resolved

MC-137749 Lag spike when crossing between chunks. Resolved

MC-137772 intense lag while trying to do anything Resolved

7 more links

Attachments

Comments 22

Greg Milson 2018-10-24T14:53:07Z

Can confirm

Shinui Lee 2018-10-24T15:42:41Z

Came here to report this. Can confirm this issue.

Jason Bailey 2018-10-24T21:14:16Z

Confirming. I have not had a crash due to this issue, so no crash report to show? It's simply lag spikes when walking between chunks.

SuperBio 2018-10-24T21:30:59Z

Similar here, use F3-G to confirm. Every time I cross from one chunk to another the game lags. It also depends on the chunk range. At 16 Chunks it's not quite as bad as say 28 chunks.

Tech Bot 2018-10-25T00:19:47Z

I can confirm

12 more comments

Andy (Romaq) Smith 2018-10-25T00:57:27Z

With F3 open, it looks like it's something to do with the "Server Light level" vs. "Client Light level". The "Server" line vanishes briefly when crossing the chunk as if the client is "wait-a-minute, let me talk with the server" even though I'm testing this in single player.

Jay Eff 2018-10-25T02:31:13Z

Can confirm, 18W43B. If I walk from one chunk to another, there's a very noticeable hesitation. If I walk back and forth between two chunks, there's the same hesitation each time I cross the chunk border.

Jacob Melton 2018-10-25T02:41:59Z

Can confirm this on 18W43B in Single Player. Does not happen on my Snapshot Testing multiplayer server.

tryashtar 2018-10-25T03:22:04Z

The pie profiler shows scheduledExecutables increasing at this time

Mindstorm38 2018-10-25T10:11:59Z

I also noticed a very high number of mob on the map, as on the screenshot. But I don't now if it's a non-bug.

McDodge34 2018-10-25T22:23:29Z

I also noticed this even while running a server on a 2nd PC, and also while just mining blocks in the same chunk, every single time you break a block, it stutters for a few seconds, I'm guessing its the new lighting engine, cause I see the same issue while just replacing the floor of a new house, every block I put down cause a slight freeze, I've tested this in the official 1.13.2 and I didn't see this problem at all.

Greg Milson 2018-10-26T10:28:16Z

Still an issue in 18w43c

McDodge34 2018-10-26T13:52:43Z

I can confirm its still in 18w43c, I'm not surprised being one of the first released snapshot for this version, perhaps it was a little bit too early, I'm blaming the new lighting engine on this one, I see the same lag for each block I mine or I put down, so I suspect its the way the new lighting engine is calculating its way out.

Jay Eff 2018-10-26T14:49:48Z

Also can confirm, still happens on 18w43c. Is the stutter happening because the new chunk data is drawn all at once as soon as it's received by the client, and the chunks behind you that are despawning are being despawned all at the same time? If all of this is happening on the same tick, then maybe it should be spread across several ticks.

Shinui Lee 2018-10-26T19:40:13Z

Can confirm this is still happening in 18w43c.

Edit: just to confirm that I agree with the person above me. The game tries to draw all the chunks at once as soon as I move to the next chunk, and I think that's part of the issue somehow.

[Mod] Neko 2018-10-26T19:40:56Z

Also can confirm in 18w43c. Reopening.

[Mod] Neko 2018-10-31T21:10:16Z

Seems to be fixed in 18w44a.

McDodge34 2018-11-01T01:10:33Z

Seems to be fixed, I can confirm, but I see a little lag spike after chopping down a tree now, its not extreme, but I think its related to the leaves despawning mechanic, which is maybe a new bug report, I'll browse through the new ones tomorrow when I have more time, if its not there, I'll try to reproduce it again and report it.

Mindstorm38 2018-11-01T10:48:00Z

I can also confirm that this is fixed. Wp devs

Makzevu 2018-11-04T13:59:23Z

Before the fix, I had a lot of lag while walking between chunks. After the fix it's been a small inconsistent spike most times. My latency when crossing chunk boarders goes up to 100-120ms (again, not as bad as before the fix, but still noticeable). But for some reason, I only get the spike if I stay in the current chunk for a few seconds. Going back and forth between the boarder quickly doesn't give me any lag.

Is this another bug like MC-132135 or MC-123584?

Ionescu Andrei 2019-09-21T15:00:32Z

this 1.14 grid frame skip bug happened to me on the released version

Pardiac Antoine 2020-07-14T12:04:56Z

is this fix ? i still have the bug on server on 1.16.1