High memory usage on linux in 1.13 snapshots

Just tested this in 17w43b, the first time running it - I thought that the bug had been fixed, but rerunning it it happened again. Tried deleting the .minecraft folder, but it still occurred. Haven't been able to get it to not happen since

Video: https://www.youtube.com/watch?v=fFjdF5RnKj8 This time I used a script to kill the process before mc tried to use too much ram, as that would freeze my pc, and last time I wasn't quick enough. Script source here https://hastebin.com/obeqamagoh.bash . Launcher log (reran it since it lookes like the launcher crashed❓ in that recording) https://hastebin.com/tuniwekuxe.txt

Just for comparison, right now 1.12.2 uses a constant 6.2 GB on the main menu (though I was sure it was less in the past)

I managed to get a heap dump with visualvm before it got killed at around 13gb. The file itself is only 93mb though, link: https://mega.nz/#!pfAElbQa!qfL7Kxt2DQ30YvxDsuBlZJCi_jDnrtrnqX4HwDc_lkA

edit: just a sidenote, sometimes it "stabilizes" and doesn't keep using more and more ram. Not sure why. The last time it happened, it was around 10.4gb. Also, I haven't been able to attempt the reproduction a lot, but it seems that it won't happen for around 5 minutes after a full restart (of the pc).

I also have the same issue. I found that if I disable memory overcommit, or set ulimit -d, and let it run out of memory, it shuts down itself with message: "Not enough memory" (and it uses about as much memory as I can give it, 4GB of ram and my 10GB of swap). I also know that this is entirely off-heap memory, so heap dump probably won't be very useful.

I also noticed that for me it sometimes works fine if the MC window is on top, but (almost? I always has runaway memory usage when the window is not on top.

I'm running it on:
CPU: Intel core 2 duo E4500 2.2GHz (I know it's ancient)
GPU: ATI radeon HD5670 (running with open source GPU drivers on linux)
4GB RAM

OS: Linux gentoo, (4.12.5-gentoo)
Java version:
java version "1.8.0_144"
Java(TM) SE Runtime Environment (build 1.8.0_144-b01)
Java HotSpot(TM) 64-Bit Server VM (build 25.144-b01, mixed mode)

I also noticed that for me it sometimes works fine if the MC window is on top, but (almost?0 always has runaway memory usage when the window is not on top.

Hm, I remember another report of this from a while ago. Going to go and try to find that...

EDIT: It's MC-99342.

MC-99342 mentions that it's java heap memory, here I'm talking about memory that isn't even managed by JVM, so it's not just the game that becomes unresponsive - it's the whole system that becomes unresponsive (to a point that it's faster to reboot). And it also happens when the window is on top, just takes more time, and doesn't always happen.

Still there in 18w11a for me...

i just tested out the new launcher and the old one. so on new launcher memory leak is there, but on the old launcher no problems...

Can Confirm for 1.13 pre release 1: My game lags very badly and is prone to freezing after playing for a while.

Can confirm for pre-release 2 and It appears both on windows and macosX. Probably linked ot terrain gen/block updates, because it doesn't affect void worlds 

Is this still an issue in Minecraft 1.13.1?