On Sun, May 24, 2009 at 7:25 PM, <helicoterus-elih@xxxxxxxx> wrote:
I perform some tests to get hard disc performance differences between HVM domU
and a paravirtualized one (both Debian Lenny).
first of all, make sure you do NOT use file:/ in domU config. At least
use tap:aio:
I used hdparm ( option -t and -T) to test cache of disc and disc sequential
read.
Syntax is:
hdparm -t|-T /dev/hda1
hdparm -t for hvm returns about 30 MB/sec, wheras hdparm -t for PV return about
180 MB/sec.
This is normal. HVM by default should have MUCH lower disk throughput.
That's why HVM domUs need PV drivers for both Linux (included by
default on RHEL/Centos 5.3, not available yet for newer kernels) and
Windows (like GPLPV).