[pve-devel] less cores more iops / speed

[Stefan Priebe - Profihost AG]

Am 09.11.2012 15:49, schrieb Alexandre DERUMIER:
> Maybe one last question (sorry ;)
>
> Do you have tried to launch 2 fio test from 2 differents kvm host at the same time ?
>
> If yes, do you have more io or do you have half of speed on each fio test ?

Only one VM active on a Single Xeon 3.6Ghz:
   write: io=6024MB, bw=68519KB/s, iops=17129, runt= 90025msec
   read : io=6057MB, bw=68891KB/s, iops=17222, runt= 90026msec
   write: io=71540MB, bw=808308KB/s, iops=197, runt= 90630msec
   read : io=147096MB, bw=1631MB/s, iops=407, runt= 90162msec


Only one VM active on a Dual Xeon 2.5Ghz:
   write: io=2224MB, bw=25285KB/s, iops=6321, runt= 90070msec
   read : io=2033MB, bw=23108KB/s, iops=5777, runt= 90078msec
   write: io=50900MB, bw=574235KB/s, iops=140, runt= 90767msec
   read : io=84228MB, bw=954499KB/s, iops=233, runt= 90361msec


Both VMs active (doing each test in parallel):

VM 1:
   write: io=5376MB, bw=61112KB/s, iops=15277, runt= 90086msec
   read : io=6092MB, bw=69292KB/s, iops=17323, runt= 90028msec
   write: io=67724MB, bw=766012KB/s, iops=187, runt= 90533msec
   read : io=160200MB, bw=1776MB/s, iops=444, runt= 90187msec

VM 2:
   write: io=2351MB, bw=26719KB/s, iops=6679, runt= 90083msec
   read : io=2190MB, bw=24899KB/s, iops=6224, runt= 90081msec
   write: io=48320MB, bw=545652KB/s, iops=133, runt= 90680msec
   read : io=88136MB, bw=999571KB/s, iops=244, runt= 90290msec

Right now i've no idea why the Dual Xeon is slower at all / in general.

Stefan