From: Anthony Liguori <aliguori@us.ibm.com>
To: Ben-Ami Yassour <benami@il.ibm.com>
Cc: kvm@vger.kernel.org, markmc@redhat.com,
Muli Ben-Yehuda <MULI@il.ibm.com>
Subject: Re: virtio performance issue
Date: Tue, 16 Sep 2008 09:16:38 -0500 [thread overview]
Message-ID: <48CFBFC6.4040405@us.ibm.com> (raw)
In-Reply-To: <1221574441.26630.19.camel@cluwyn.haifa.ibm.com>
Ben-Ami Yassour wrote:
> I am running virtio with the latest KVM code, and see a significant
> performance issue.
>
> Ping to the host (or any other close machine) reports a 4ms delay.
>
What kvm version and what host kernel version?
It's very easy to mistakenly compile qemu without GSO support too. You
have to make sure that the 2.6.27 if_tun.h is being included by QEMU.
Regards,
Anthony Liguori
> In the same setup with an e1000 emulation (just changing model=virtio to
> model=e1000 in the KVM command line), ping reports 0.177ms delay.
>
> BTW, initially I saw that the throughput when using netperf is very low,
> even from guest to host, even though the CPU utilization is low.
>
> What might be the problem?
>
> Thanks,
> Ben
>
>
next prev parent reply other threads:[~2008-09-16 14:17 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-09-16 14:14 virtio performance issue Ben-Ami Yassour
2008-09-16 14:16 ` Anthony Liguori [this message]
2008-09-16 19:24 ` Ben-Ami Yassour
2008-09-17 10:49 ` Mark McLoughlin
2008-09-17 12:10 ` Ben-Ami Yassour
2008-09-16 17:43 ` Bernhard Schmidt
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=48CFBFC6.4040405@us.ibm.com \
--to=aliguori@us.ibm.com \
--cc=MULI@il.ibm.com \
--cc=benami@il.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=markmc@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.