I very recently swapped from Core to Scale along with a hardware change. I will start by noting this is a fresh install, and I am running no apps. I am seeing a strange behavior within scale causing the system to become unresponsive, or completely crash in some instances. When performing a backup…

Can you get us a bug ticket and debug file from the system when it starts to become unstable? With no Apps, I would have to assume something is consuming memory and not releasing. (ZFS or NFS is likely). You can also kickoff an htop and watch it in real-time to see what is holding it.

As far as here on the forums, would be useful to see the complete Scale hardware list.

Will do, I’ll be free to replicate the issue and pull debug files first thing tomorrow. Cheers.

Hard to say. This htop screenshot doesn’t show a system that has run out of memory yet, it’s barely half used. ARC is by design supposed to use as much RAM as is available. Unused RAM is wasted RAM. But its also supposed to give it back and shrink as other services reserve more.

How many VMs are you running on the server and how much memory have you commited to them?

I have 8 VMs with 64G commited to them.

I think ARC using the whole of the available system memory is a good thing providing it works correctly. If you check /var/log/messages are you seeing OOM-Killer invoked at all killing these processes due to memory pressure?

Hi kris. I spent some time replicating the issue tonight and got a bug ticket submitted. I had to submit it post reboot as replicating the issue causes the system to crash to a grub prompt immediately now, so I cannot obtain it mid-issue. I hope that it is still of some use. I’ve also replicated …

Thanks, got the ticket here. We’ll take a look at it!

ZFS_ARC_MAX issue - out-of-memory errors in kernel with Scale 24.04.1.1

TrueNAS General

Spunky17 June 10, 2024, 4:45pm 5

wondering if this is related to what i’m seeing. i’m getting similar symptoms with the GUI and SSH going unresponsive. my last crash i saw my ARC get up almost my entire memory footprint.

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ZFS_ARC_MAX issue - out-of-memory errors in kernel with Scale 24.04.1.1

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