BDS-355Entering the Nether creates permanent server lag until restart
My server generally runs fine until a player enters a Nether portal, after which the lag increases (or maybe tick rate drops?) significantly. Mobs and players become extremely choppy and block updates (e.g., mining/harvesting) take excessively long to process. This lag persists in the overworld even when players return from the Nether. All clients are on modern Windows 10 PCs and run fine before entering the Nether, so it's not likely a client problem. The only way to clear the lag seems to be to restart the server.
Environment
BDS 1.8.0.24 on Ubuntu 18.04 Server
Comments9
History1
Resolution: Unresolved → Invalid
Also, server CPU normally runs around 20-25%, but spikes to 100% when the Nether is entered, then drops again to normal after "generating terrain" completes on the client.
I think I need to further profile CPU/memory as users grow as well. Testing with single player on server, it's not happening.
I added memory and the server is still lagging. CPU usage is <25% and memory usage on the host is less than 75% (swap partition space isn't even touched yet), and I'm still getting the lag.
We have the same problem. When ever someone is entering the Nether the server starts lagging like crazy. It does how ever goes away when people leave the Nether.
Also affected on 1.8.1.2 on Ubuntu 18.04 LTS, I've been testing and one single CPU core gets pegged to 100% once someone reaches a specific area of the nether. It will however go back to normal if everyone exits/re-enters. It will also immediately trigger again once players take a few steps in one direction.
Memory remains stable the whole time. Restarting the server while someone is in the nether doesn't seem to help either, as they will immediately trigger the condition again.
Updated to 1.9.0.15 which released today, the problem is still present and somewhat amplified – whenever someone loads a dimension of any kind (on connect or through a portal), now all CPU cores of my server are pegged to 100% for an unreasonably long while, and the tickrate gets really horrible. It eventually stabilizes.
The nether seems to still peg a single core to 100% depending on where you stand inside it.
You are probably experiencing the effects of mobs not despawning bug do a kill command to pigman and ghasts. that should clear your lag
I went in and /kill'd all entities, upon return new mobs had spawned in and the problem is indeed gone for now.
Thanks!
Looks like this one got sorted!
Could a mod please close this issue.