Strange disk performence in Windows guest

[mercury131]

Hello everyone!

I have proxmox home lab, and now I try to choose filesystem for my virtual machines.
I will run Windows VMs and I need better filesystem for that.

I setup Windows VM with this config:

agent: 1
balloon: 0
bootdisk: virtio0
cores: 4
cpu: host
memory: 4096
name: Test-IOPS
net0: virtio=A6:62:8E:A2:02:B7,bridge=vmbr0
numa: 0
ostype: win10
scsihw: virtio-scsi-pci
smbios1: uuid=206d4f33-dbf2-4a33-a9b9-0622092a7897
sockets: 1
virtio0: Silver:vm-109-disk-1,size=30G
virtio1: Gold:vm-110-disk-2,size=30G

and I test this filesystems:
ext4
xfs
brtfs
zfs
LVM (without any fs, not thin LVM)

I run ATTO Disk Benchmark inside VM on this filesystem and I have very strange results =(
My test hard drive is - WDC WD10EARS-00Y5B1
(5400 RPM 64MB Cache,SATA 3.0Gb/s)

I run tests on virtio1 disk without Windows OS (empty disk formatted NTFS)
Now my test results inside VM :

ext4 (qcow2)

XFS (qcow2)

BTRFS (qcow2)

ZFS (pool, no compression)

LVM (not thin)

I dont understand how ext4,xfs and btrfs got 8GB/s speed on this hard drive?
Maybe its cache magic?
And why zfs and lvm got poor performance onlike ext4,xfs and btrfs ?

What I do wrong and what is filesystem got best performance?

Thanks in advance!

 

[Alexander Pytlev]

Small file size to test (256Mb), try to 4Gb and check.

 

[mercury131]

Small file size to test (256Mb), try to 4Gb and check.

Hello Alexander!

I recheck my tests on ext4 and zfs

Results here:

ext4

ZFS (pool, no compression,8k block size in proxmox, ashift=12)

As you can see zfs is slower than ext4 on same hard drive.
I think file size doesnt matter.

I don't understand why zfs slower in this test.

 

[scintilla13]

ZFS looks slower than anything out of the box in Proxmox.
In my case is unusable. Just moving the virtual disk to a single XFS HDD gots workable results.
The RAIDZ 4 SSD zpool was so slow to put the VM on it, unable to work.
So ZFS is able to make slower what is physically faster.
Otherwise, I read a lot of articles reporting good RAIDZ performance also on legacy hardware (but always based on freebsd).

I believe that Proxmox Wiki should contain a clear troubleshooting pattern to make ZFS performances decent.
This forum has plenty of posts related to poor ZFS performances, but no one of them reports a clear troubleshooting path.
Most of the time the fault is charged to the hardware.