Bloody windows performance issues

[mfpck]

Hi,

Running pve on a dell r330 with an hw. h730 and 8 enterprise ssds as a raid 10 (no read ahead and write back) - Xfs, lvm:thin and raw disk images.

For my Windows guests I followed this guide;
https://pve.proxmox.com/wiki/Windows_10_guest_best_practices

and this:
https://pve.proxmox.com/wiki/Performance_Tweaks

Btw. Linux guests are fine even with default settings.

Because I observer general performance issues on Windows guests but basicaly regarding disk operations I may change the follwoing settings:
hw raid to write through = fastpath ?
virt harddisk to default, so cache none, so no write back or even writethrough ?
Disable Ballooning? If so should I also deinstall the driver itself from the guest?

Thread '[SOLVED] Hyper-Threading vs No Hyper-Threading; Fixed vs Variable Memory'

Nov 6, 2014

After reading countless discussions, articles, whitepapers and not finding suitable answer, I decided to take matter in hand and do some testing to come to conclusion, if i should be using Hyper-Threading or not. While trying to find this answer, i also found the answer of using Fixed or Variable Memory for VMs in Proxmox.
[[Disclaimer: These are all based on my testing and configuration so my opinion may be biased towards my virtual environment]]

Short Answer
-YES!! Use Hyper-Threding whenever possible, even on a newer multi CPU node.
-Use Fixed memory allocation in VMs where performance...

• wahmed
• Replies: 46
• Forum: Proxmox VE: Installation and configuration

• 

Alternative I think about to switch to zfs....

Hope if someone could help here -
Thx and Best!

 

[Fantu]

Can be good to post the vm configuration (at least one of the windows with performance issue).

qm config <vmid>

If the writings are not too sustained perhaps with zfs, lots of ram usage (for zfs cache) and good zfs optimizations you can have performances improvements while if they are sustained and with a continuous bottleneck on the disks already now with vm disk on lvm and raw I suppose that with zfs you would get worse (because you would have an extra filesystem in the middle and on that is also cow that amplifies the writings)

 

[mfpck]

agent: 1
bootdisk: scsi0
cores: 8
cpu: x86-64-v2-AES
machine: pc-i440fx-8.1
memory: 24592
name: bim21
net0: virtio=BC:24:11:9C:DB:4A,bridge=vmbr0,firewall=1
numa: 0
onboot: 1
ostype: win10
scsi0: local-lvm:vm-200-disk-0,cache=writeback,discard=on,iothread=1,size=1500G,ssd=1
scsihw: virtio-scsi-single
sockets: 1

looks not too bad but it performs badly...Is it good practive to update the machine typ from time to time (but it will break the windows licence) & update the virt-tools ? So many thing I could do...I think it is a Windows issue ;-)

 

[toomanylogins]

I have found setting the cpu to host and numa on helps a bit.

 

[mfpck]

I have found setting the cpu to host and numa on helps a bit.

Yes, I could try...thx. Does it break windows and the licence or just if I change the machine verion ?

 

[guruevi]

Did you set the disk to VirtIO? You need to install the guest drivers but performs a lot better. What version of guest drivers did you install?

I set the machine to q35 as well, the CPU similar to what my host is (the v2 in your config is relatively old).

Windows does consume quite a bit of disk bandwidth when doing “nothing”, you can tune that a bit if it is causing issues. You can also play with the cache options.

 

[Fantu]

The virtioscsi is visible from configuration, one thing to check is the virtio version, if >0.1.208 and < 0.1.266 there is important issue with disk driver and can cause also performance issue from what I saw.

 

[mfpck]

Ok. I will try to change the cpu to host + enable numa.
Why should changing the machine type to q35 is optimising performance ?

On this guest the virtio version is 0.1.248 but on other Win guest its up2date which are also perform not great but thanks for this special info regarding verions and issues....