VMs freeze or shut down

[NOIDSR]

Hey guys, I am a new in proxmox and Linux but need to solve the following problem. I run Win10 and MacOS VMs as well as Ubuntu VM as a server. When I copy large files from one disk to another or I do heavy video rendering my OS freezes in the middle of a transfer and cannot finish the task or rendering stops and machine freezes then maybe unfreeze and continues but everything gets very slow or VM is shut down. Or if I connect external source such as camera and start downloading files from it, time to time camera would get ejected and connected again in a few second and of course downloading stops. Same on different VMs with different OS. If I don't do anything crazy heavy everything runs normally. RAM memory is enough, I've got 64Gb, CPU i7, all drives are SSD. I would appreciate any help on troubleshooting. Thanks!

 

[bobmc]

Some system specs would be helpful

what about the result of

free -g

and

pveperf

 

[NOIDSR]

Here you go, these numbers captured when only Ubuntu server VM (memory allocated 8Gb) was running:

root@V1:~# free -g
total used free shared buff/cache available
Mem: 62 9 52 0 0 52
Swap: 0 0 0

root@V1:~# pveperf
CPU BOGOMIPS: 92796.32
REGEX/SECOND: 4741436
HD SIZE: 1162.61 GB (rpool/ROOT/pve-1)
FSYNCS/SECOND: 421.88
DNS EXT: 1002.45 ms
DNS INT: 1001.46 ms (local)

These numbers captured when I I started another MACOS VM (memory alocated for this VM is 40Gb, no ballooning) and was performing a heavy file copying and when OS slowed down almost frozen:

root@V1:~# free -g
total used free shared buff/cache available
Mem: 62 52 5 0 4 9
Swap: 0 0 0

root@V1:~# pveperf
CPU BOGOMIPS: 92796.32
REGEX/SECOND: 4887843
HD SIZE: 1162.61 GB (rpool/ROOT/pve-1)
FSYNCS/SECOND: 6.16
DNS EXT: 1005.09 ms
DNS INT: 1001.13 ms (local)

Thanks!

 

[bobmc]

My guess would be overcommitted RAM allocation, you're probably passing the GFX card through to the MACOS VM? so the ram allocation is reserved and not dynamic. Try reducing the memory allocation for the VM

 

[bobmc]

Also, your FSYNC numbers are not great (not using SSD or nvme?) and your DNS settings need looking at (should not be >100ms)

 

[NOIDSR]

I reduced VM memory from 40Gb to 30Gb and it did not change much. Copying 10Gb from internal SSD to OS first 4Gb took 2 sec and then got stuck for maybe 5 min until completed the rest slowly in chunks. All my drives are SSD or nvme. 3 aray for PVE and each VM has its own dedicated 1T SSD or nvme.
How do I troubleshoot further to see why FSYNC and DNS numbers are not good? Thanks!