I'm running 1 domU on my dom0, and both are largely idle. They're running on a
dualcore Opeteron, so I don't suspect the cpu is the bottleneck.
I'm using phy: in my domU config.
I notice (with large scp copies, at least) that writing to the domU starts off
at network speed, but then slows down to about 2MB/s after ~10 seconds,
presumably as buffers fill up. Looking at vmstat on the domU shows 100% cpu
wait, and on the dom0 at the same time, I see almost 100% idle, with the
occasional 1% system.
Have any of you tweaked your xen scheduling?
On Tue, 23 May 2006, Stephen C. Tweedie wrote:
Hi,
On Tue, 2006-05-23 at 08:55 -0700, Ben wrote:
Well, this gives me hope that I'm suffering from some kind of
misconfiguration issue. I'm using LVM-backed domUs, and I see
dom0 hdparm-t: 53.68 MB/sec
domU hdparm -t: 18.39 MB/sec
"top" and "xm top", perhaps? If you have fast storage and slow CPUs,
you may be seeing the system struggle to keep the IO pipeline between
domU and dom0 full enough to saturate the disk, for example.
Another thing, are you using "phy:" or "file:" on the domU config?
--Stephen
