Sluggishness/unresponsiveness in domU and dom0 when VM runs out of free memory

[0spinboson]

Qubes OS version:

R4.0

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Steps to reproduce the behavior:

Assign a given amount of memory to a VM (say 4GB), make the VM run out of memory (youtube videos, interactive/heavy websites), get sluggishness / stutter both in domU and dom0.

Expected behavior:

Graceful handling of this, no sluggishness/stutter bleeding into dom0.

Actual behavior:

VM becomes sluggish in a way that I never ran into on R3.2 / on R4 roughly prior to when the Spectre/MD stuff 'happened'. More importantly, dom0 also becomes intermittently unresponsive, which should just not happen. Video playback also

General notes:

Ryzen 5 1600, 32GB ram. dom0 kernel 4.15.6

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Related issues:

[0spinboson]

A related symptom: after about 10m of video playback in a VM, the entire system freezes (including cursor). only fix being a hard reboot.

[0spinboson]

A related symptom: after about 10m of video playback in a VM, the entire system freezes (including cursor). only fix being a hard reboot.

[lunarthegrey]

What is your system load like when you check in dom0 (when this happens)?

[lunarthegrey]

What is your system load like when you check in dom0 (when this happens)?

[0spinboson]

basically idle in dom0, not very busy inside the VM either; the VMs that have the issues only have 4 or 8 threads (out of 12) assigned, and they're never all that busy when this occurs; total memory used also way below the maximum (generally at least 8gb unreserved).

[0spinboson]

basically idle in dom0, not very busy inside the VM either; the VMs that have the issues only have 4 or 8 threads (out of 12) assigned, and they're never all that busy when this occurs; total memory used also way below the maximum (generally at least 8gb unreserved).

[lunarthegrey]

Have you checked logs like /var/log/messages, syslog on the VM? Anything in /var/log/xen/console/hypervisor.log in dom0?

[lunarthegrey]

Have you checked logs like /var/log/messages, syslog on the VM? Anything in /var/log/xen/console/hypervisor.log in dom0?

[0spinboson]

I did. I don't see anything there that screams impending doom to me, though.

[0spinboson]

I did. I don't see anything there that screams impending doom to me, though.

[lunarthegrey]

Maybe @marmarek would know how to debug this better.

[lunarthegrey]

Maybe @marmarek would know how to debug this better.

[0spinboson]

seems to have been due to hardware acting up.

[0spinboson]

seems to have been due to hardware acting up.