From: David Miller <davem@davemloft.net>
To: herbert@gondor.apana.org.au
Cc: netdev@vger.kernel.org
Subject: Re: GRO after RPS?
Date: Sun, 25 Apr 2010 18:17:57 -0700 (PDT) [thread overview]
Message-ID: <20100425.181757.10149105.davem@davemloft.net> (raw)
In-Reply-To: <20100426004934.GA12525@gondor.apana.org.au>
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Mon, 26 Apr 2010 08:49:34 +0800
> On Sun, Apr 25, 2010 at 05:09:33PM -0700, David Miller wrote:
>>
>> Herbert, after thinking about some ideas we've been discussing and
>> some suggestions from folks like Tom Herbert, I'm thinking of changing
>> it such that we do GRO after RPS sends the packet to a remove cpu.
>
> Actually, I'd've thought that doing GRO before RPS would be a
> better solution as it means that RPS would have a lot less work
> to do.
Either GRO walks the skb->rxhash values one by one, or GRO does, the
cost is going to be roughly equivalent I think.
And when the packets do match, you can't just trust the ->rxhash in
the GRO code, since a hash match only indicates that the packets might
have the same flow. So you're going to have to touch the packet
headers in that case on the pre-RPS cpu.
The goal is to eliminate all packet header references from the pre-RPS
path, and let the post-RPS cpu do it.
next prev parent reply other threads:[~2010-04-26 1:17 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-26 0:09 GRO after RPS? David Miller
2010-04-26 0:49 ` Herbert Xu
2010-04-26 1:17 ` David Miller [this message]
2010-04-26 1:40 ` Changli Gao
2010-04-26 1:47 ` Herbert Xu
2010-04-26 1:41 ` Herbert Xu
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=20100425.181757.10149105.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=herbert@gondor.apana.org.au \
--cc=netdev@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;
as well as URLs for NNTP newsgroup(s).