Re: Xen Dom0 vs. DomU disk I/O

[Bartek Krawczyk <bbartlomiej.mail%gmail.com@localhost>]

You should add "conv=sync". Then you'll sync the buffers to the filesystem properly.

WIth conv=sync I get:

Dom 0 - Debian Squeeze amd64: 382MB/s

Dom U - Debian Squeeze amd64: 250MB/s

Dom U - NetBSD 6 amd64: 315MB/s

NetBSD is a PV guest. Debian is running 2.6.32-5-xen-amd64 kernel so I suppose it's also a PV.

Without conv=sync I get ~600MB/s on Linuxes DomU/Dom0 and ~300MB/s on NetBSD DomU

Regards,

On 22 November 2012 07:54, Stephan <stephanwib%googlemail.com@localhost> wrote:

Hi,

both Dom0 und DomU are NetBSD 6.0 amd64 release. The hypervisor is Xen 4.1 from current pkgsrc. The filesystem is a default FFSv2:

/dev/xbd0a on / type ffs (log, local)

I have done the testing like this:

vm00# dd if=/dev/zero of=myfile bs=64k count=1000
1000+0 records in
1000+0 records out
65536000 bytes transferred in 11.493 secs (5702253 bytes/sec)

On the Dom0 I see this:

bsd1# dd if=/dev/zero of=myfile bs=64k count=1000
1000+0 records in
1000+0 records out
65536000 bytes transferred in 0.672 secs (97523809 bytes/sec)

Regards!

2012/11/21 Bartek Krawczyk <bbartlomiej.mail%gmail.com@localhost>

How do you test your HD throughput under Dom0 and DomU? I have a Linux Dom0 with a NetBSD 6 DomU PV. I can test this at my site and report the results.

--
Bartek Krawczyk
network and system administrator

--
Bartek Krawczyk
network and system administrator