Steam client leaking shared memory

[acuifex]

Your system information

• Steam client version: Feb 22 2023 at 20:36:05
• Distribution: arch linux 6.1.12-arch1-1
• Opted into Steam client beta?: Yes
• Have you checked for system updates?: Yes

Please describe your issue in as much detail as possible:

this is mostly a copy of https://steamcommunity.com/groups/SteamClientBeta/discussions/0/3775742652420260102/
i'm making an issue here too because i'm not sure if the forum is used, and because i like feedback.

Steam is leaking memory when launching and exiting. Around 100 MiB per launch. This happens both on stable and beta.
i don't know for sure what process is leaking memory, since ipcs and other commands don't really give any useful output.
i've ran sudo pacman -Syu and rebooted the system, but the issue persists.

Steps for reproducing this issue:

1. ls -1 /dev/shm | wc -l
2. df -hl -t"tmpfs"
3. take note of the counts
4. launch steam client
5. exit steam client with steam->exit
6. repeat 4 and 5 a few times for noticeable impact
7. repeat 1 and 2, and compare them to 3

[acuifex]

i've just checked, it also happens when launching and exiting team fortress 2. i assume it has something to do with the embedded browser.

[acuifex]

okay it also happens with and without steam overlay enabled, and it happens in tf2 and JBMod both on beta and stable. Some uncleared game cache i assume?

[b3noist]

Arch 6.2.1-arch1-1, non-beta here and seeing similar things happening. Also, RAM usage for Steam just seems to be growing in general over time for little reason.

[holyjoespb]

Each start CSGO increases the size of /dev/shm by ~60MB
Stable steam, Ubuntu 22.04 6.1.15-tkg-cfs https://gist.github.com/holyjoespb/71baf2b68849635ff6866014569b92a8

[dakrk]

I have my computer on for such an amount of time that earlier today I noticed I had over 6GB used by files in /dev/shm. This wasn't immediately noticeable either as it's not in an actual process by a user and as such isn't visible in a usual system monitor program. I imagine this could cause quite a bit of pain for other users that won't suspect to check the usage of a tmpfs and they just reluctantly resort to rebooting.

This doesn't seem to be a new issue either, with #3378 dating all the way back to 2014 (almost a decade ago!)

[h1z1]

It's not quite a traditional memory leak, more like a temporary file on a ramdisk being used as a pipe. You can lsof /dev/shm/fileglob to confirm they are infact left over in which case you can remove them without rebooting. It's a bit more complicated if they are still in use. If it's clearly something related to a game or steam and you have neither running then it's a bigger bug.

[tomjaguarpaw]

Wow, I've just hit this. It's appalling behaviour. I was rapidly running out of memory and confused about why. But I'm glad to know I can safely delete those files.

[lemmi]

Same issue on voidlinux.

[143mailliw]

Same issue on Arch. Still a problem.

[cwrau]

Same issue here, I just cleaned ~10G of files in /dev/shm which were created by steam, which still existed after I stopped Steam

[grinapo]

Intersting. Indeed, Steam Electron UI secretes a huge amount of very large files in /dev/shm/, which is a horrible behaviour in itself, since /dev/shm/ is not for "normal" temporary file storage for various reasons already readable throughout the net.

Lots of u1111-Shm_b8fe91eb files (uid 1111), 26 MB in size for me, here and now. Steam client was not even crashing, it was Quit'ed nicely, the files still left behind. (Well, originally anyway.)

Let me tell you what it does, though.
When /dev/shm/ gets full (and eventually it does), and one do not notice, everything based on electron will segfault. No error message, no console message, no nothing: crash. It may crash in various libs, but for me most often it was the infamous sandbox lib aka. libcef.so, which already causes some grief for the UI developers, judging by some console messages.

You may say, hey, who uses Electron? I don't even know what it is! - Oh well, you'll see. A lot. Start with everything chrome based, then everything web based having a local desktop client. I can't even try listing the damn beasts.

So, obviously, Steam client instantly crash, with no messages apart from the crashdump, which contains no pointers to the real cause whatsoever.

Debugging that problem is close to impossible. If you don't notice /dev/shm is full you can pull your body hair out. I was lucky to start a different program with nicely told me that cannot write /dev/shm, no space left on device. Deleting the extreme amount of crap immediately fixed the systemwide issue (after spending half a day on it).

So yeah, this is no good, and it is possibly related to electron, but I cannot possess enough info to specify.