IO Delay almost 100%

[Dexter23]

Hi everyone
After create a 4th vm with windows 10 in proxmox dashboard i see io delay very high, and the windows 10 vm is very slow.
Disk are 2 SSD 1 tb, i have other customer with the same machine with windows vm and i have no problem.
Is there a method to understand why io delay is very high?
Thanks

This is the dashboard:

 

[ness1602]

Usually bad disks,eg consumer samsung, etc.

 

[Dexter23]

I don't think so, because if i turn off this vm the server io delay stil aroud 0-5 %, btw the ssd are Crucial

 

[Chris]

btw the ssd are Crucial

Please provide the exact model, Crucial is not specific enough... But yes, probably bad SSD performace. You can check which process is causing the io with tools such as iotop.

Also you might want to install the latest qemu-guest-agent in your VM and enable trim support if not already done, regularly flushing unused blocks can help with write performance.

 

[Dexter23]

Hi this is the disk:


As i mention above in the 1st post i have already other 3 customer with the same server and disk with windows 10 vm and other 3 vm linux and i don't have any io delay.
With iotop the io delay is caused by windows vm, as i said above if i turn off this vm the io delay consume back to normal use.

 

[Chris]

The BX500 is not at all a performant drive and it comes without cache, see https://www.tomshardware.com/reviews/crucial-bx500-ssd,5377-2.html

So depending how much write load you will have, the performance can get pretty bad for these disks. Enterprise level SSDs are recommended because of this issues with consumer class SSDs.

 

[Dexter23]

Ok i know this are consumer ssd and not enterprise but for example on this another customer with the same hardware:

And this disk:


This ssd are Western Digital Blue, i don't have any issue with IO Delay.

 

[Nuke Bloodaxe]

Just thinking, could you show the hardware page for each VM? [The more information available, the more people have to work with.]
As a suggestion, you could also have a look at your customer's settings as well, for comparison.

 

[Chris]

This ssd are Western Digital Blue, i don't have any issue with IO Delay.

Ok, so not the same hardware, these seem to have at least a cache which helps with performance, see https://www.tomshardware.com/reviews/western-digital-blue-ssd-review,4767.html

 

[Dexter23]

I destroy the vm, i want to download again windows10 iso from website microsoft and reinstall from zero....anyway for reference i have try different combination, machine i leave default i440fx i tru with q35 also but nothing change, SCSI Controller i use VirtIO SCSI, Disk are configure as SCSI Device, i try both cache: default(no cache) and write back and option "discard" tick and untick but the io delay still high.

 

[Dexter23]

@Chris
What modell of SSD with good rapport of quality/price do you recommend to buy?

 

[LnxBil]

What modell of SSD with good rapport of quality/price do you recommend to buy?

Any enterprise SSD will work.

 

[leesteken]

What modell of SSD with good rapport of quality/price do you recommend to buy?

Make sure that it has PLP. I'm recently very happy with a Micron 7450 M.2

 

[Dexter23]

Ok Thanks