From: Brian Jackson <iggy@theiggy.com>
To: Erik Brakkee <erik@brakkee.org>
Cc: kvm <kvm@vger.kernel.org>
Subject: Re: network performance between host and guest...
Date: Fri, 17 Dec 2010 17:57:53 -0600 [thread overview]
Message-ID: <4D0BF901.5020503@theiggy.com> (raw)
In-Reply-To: <4D0BE42E.6010309@brakkee.org>
On 12/17/2010 4:29 PM, Erik Brakkee wrote:
> Hi,
>
>
> For a backup of data from a VM to a USB mounted disk I want to
> circumvent the USB 1.1 limitations on the guest and instead copy the
> data over to the host using scp/ssh. I have setup a network using
> virtio and NAT like this:
>
> <interface type='network'>
> <mac address='52:54:00:6b:0d:36'/>
> <source network='default'/>
> <target dev='vnet1'/>
> <model type='virtio'/>
> <alias name='net1'/>
> <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
> function='0x0'/>
> </interface>
What does that equate to in command line options? Check libvirt logs
maybe. What version of qemu-kvm? Guest details? Host details?
>
> When I now create a 1GB file using dd and copy it over from the guest
> to the host, I am seeing a performance between 25-30 MB/s.
Is it to and from the same disk? If so, maybe you could try a tmpfs in
the guest or host so you aren't constantly seeking back and forth on the
same disk.
Also have you tried something like rsyncd instead of scp? Maybe you are
hitting some sort of encryption limitation.
>
> My question is if this is normal because I have seen others on the
> internet achieve far greater speeds.
Depends on a lot of factors. Certainly raw bandwidth wise, virtio-net is
capable of a lot more than that. With vhost-net here, I can get over
5gbps guest to host. And that's on crappy old first gen cpus (no ept/etc.).
>
> In any case the speeds are comparable to current USB 2.0 speeds but I
> intend on using USB 3.0 so would like to get a little bit more out of it.
>
> What would I use to speed this up a bit futher?
>
> Cheers
> Erik
>
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2010-12-17 23:57 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-17 22:29 network performance between host and guest Erik Brakkee
2010-12-17 23:57 ` Brian Jackson [this message]
2010-12-18 23:03 ` Erik Brakkee
2010-12-19 18:39 ` network performance between host and guest/iscsi to the rescue Erik Brakkee
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=4D0BF901.5020503@theiggy.com \
--to=iggy@theiggy.com \
--cc=erik@brakkee.org \
--cc=kvm@vger.kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox