From: Rusty Russell <rusty@rustcorp.com.au>
To: Qin Chuanyu <qinchuanyu@huawei.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
jasowang@redhat.com, KVM list <kvm@vger.kernel.org>
Subject: Re: [PATCH] virtio: make udp more efficient by avoiding indirect desc
Date: Thu, 13 Feb 2014 13:27:44 +1030 [thread overview]
Message-ID: <87a9dvg1nb.fsf@rustcorp.com.au> (raw)
In-Reply-To: <52FA3AAC.2050003@huawei.com>
Qin Chuanyu <qinchuanyu@huawei.com> writes:
> udp packet use 2 buffers at least, one for vnet_hdr and
> one for skb->data.
> we could change the threshold from 2 to 3, so the udp packet
> which data buff only using single desc will gain from this.
> the guest would avoid from allocating memory dynamically.
> the host would avoid from translating indirect desc.
>
> Signed-off-by: Chuanyu Qin <qinchuanyu@huawei.com>
We should really adapt the threshold depending on how full the ring is.
If it's gotten cramped recently, prefer indirect. See linux/average.h.
Such a change would have to be benchmarked carefully though!
Cheers,
Rusty.
prev parent reply other threads:[~2014-02-13 4:40 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-11 14:58 [PATCH] virtio: make udp more efficient by avoiding indirect desc Qin Chuanyu
2014-02-11 15:43 ` Michael S. Tsirkin
2014-02-12 1:51 ` Qin Chuanyu
2014-02-12 8:59 ` Paolo Bonzini
2014-03-03 11:22 ` Qin Chuanyu
2014-02-13 2:57 ` Rusty Russell [this message]
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=87a9dvg1nb.fsf@rustcorp.com.au \
--to=rusty@rustcorp.com.au \
--cc=jasowang@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=mst@redhat.com \
--cc=qinchuanyu@huawei.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.