Speed Issue KVM Network NFS Mount

[informant]

Hi all, a question on all. I hope you can help me.

On my Hostsystem i have connect a Storage with GBit and mount this with nfs. Speed are here 99-110MB/s. On same Host i have install a KVM Server with Debian and have mount the same Storage. But if i make the same test here, i have only 1/4 of speed. Max. 30 MB/s. Why this and how can i reach the same speed, or faster as the host?

regards

 

[informant]

Hi, here is a link with same problem and a solution -> http://serverfault.com/questions/407842/incredibly-slow-kvm-disk-performance-qcow2-disk-files-virtio

but, how can i configure this in proxmox to have speed on my KVM server?

regards

 

[dietmar]

but, how can i configure this in proxmox

Those are the default settings (or what do you want to configure exactly?).

 

[informant]

hi dietmar,

thanks for answering on weekend. i look for a option to get more hdd-speed in virtual maschine.

regards

 

[dietmar]

You can see the actual kvm command line with:

# qm showcmd <vmid>

If you want to test new option, you can copy and modify that command line, then start manually using that new command line.
But as mentioned above, we already use optimal settings.

 

[dietmar]

Besides, what benchmark and cache mode do you use?

 

[informant]

hi, thanks for information.

tested i have with dd and a hdd-benchmark test script of http://juliusbeckmann.de/.

regards

 

[manu]

Are you using virtio network drivers on guest system ?

 

[informant]

hi manu,

i have test intel and virtio driver. all the same issue.

regards