[libvirt] [PATCH v3] Add support for virtio-net.tx_queue_size

Peter Krempa pkrempa at redhat.com
Wed Aug 2 11:27:28 UTC 2017


On Wed, Aug 02, 2017 at 12:44:37 +0200, Michal Privoznik wrote:
> https://bugzilla.redhat.com/show_bug.cgi?id=1462653
> 
> Just like I've added support for setting rx_queue_size (in
> c56cdf259 and friends), qemu just gained support for setting tx
> ring size.
> 
> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
> ---
> 
> diff to v2:
> - rebase to current HEAD
> 
> There's no fundamental change since v1. It's just discussion on this patch that
> makes me send newer versions because the older ones do not apply cleanly
> anymore.

[...]

> diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
> index 91195be0b..47e21c10d 100644
> --- a/docs/formatdomain.html.in
> +++ b/docs/formatdomain.html.in


> @@ -5204,6 +5204,20 @@ qemu-kvm -net nic,model=? /dev/null
>          <b>In general you should leave this option alone, unless you
>          are very certain you know what you are doing.</b>
>        </dd>
> +      <dt><code>tx_queue_size</code></dt>
> +      <dd>
> +        The optional <code>tx_queue_size</code> attribute controls
> +        the size of virtio ring for each queue as described above.
> +        The default value is hypervisor dependent and may change
> +        across its releases. Moreover, some hypervisors may pose
> +        some restrictions on actual value. For instance, latest
> +        QEMU (as of 2017-07-13) requires value to be a power of two

In v1 I've pointed out, that you should use a proper qemu version rather
than the date, which does not really tell anybody which version supports
this new thing.

> +        from [256, 1024] range.
> +        <span class="since">Since 3.6.0 (QEMU and KVM only)</span><br/><br/>

Also since you've reposted after the release, you could have bumped this
to the proper version.

> +
> +        <b>In general you should leave this option alone, unless you
> +        are very certain you know what you are doing.</b>
> +      </dd>

As I've said earlier. I'm not willing to give an ACK to this, so a
different reviwer will need to step in. I just wanted to point out the
mistakes in the docs.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20170802/727e8771/attachment-0001.sig>


More information about the libvir-list mailing list