Performance issues in same hardware

[costasppc]

Hello,

We have 2 installations of PVE 8.4.14 on 2 x DELL SERVER PE R360 XEON 6353P/32GB/480GB/H755, using 2 disks as RAID1 (on the controller). In each of the PVE we have a Windows Server 2025 machine, with identical specs and setup (2 different sites), lets say 02 and 03.

We started to have complaints from the 03 site, and started digging, we find out that the PVE and the VM on site 03 are acting slow (see pveperf attached images on 02 and 03).

We checked the VMs inside using the same diskspd command (maybe the block size should be change, but we wanted to see how they will react):
diskspd -b256K -d120 -h -L -o2 -t4 -r -w30 -c250M c:\io3.dat
and there is a huge difference there as well (see attached images).

Also attaching images of the VM setups, maybe we missed something there.

Any help will be greatly appreciated.

Best regards

K

 

[alexskysilk]

change cpu type to x86-64-v2-AES (or v3)

 

[costasppc]

Thank you,

Will this help on disk performance issues?

Best regards

K

 

[alexskysilk]

Maybe. if the speed on the host is the same, the issue is with the disk subsystem. check cache setting.

 

[costasppc]

Thank you,

Cache is writeback on both VMs.

best regards

K

 

[alexskysilk]

I meant on your raid controller.

Start by checking whether you can run your performance test on each HOST and see if the results are the same.

 

[costasppc]

Thanks, i will check the raid controller tomorrow and get back.

Best regards

K