From: "Michael Chan" <mchan@broadcom.com>
To: "Roland Dreier" <rdreier@cisco.com>
Cc: "David Miller" <davem@davemloft.net>,
ak@suse.de, krkumar2@in.ibm.com,
"netdev" <netdev@vger.kernel.org>
Subject: Re: [RFC] New driver API to speed up small packets xmits
Date: Tue, 15 May 2007 15:05:28 -0700 [thread overview]
Message-ID: <1179266728.25622.46.camel@dell> (raw)
In-Reply-To: <adaps51pzg8.fsf@cisco.com>
On Tue, 2007-05-15 at 14:08 -0700, Roland Dreier wrote:
> > > Well, IPoIB doesn't do netif_wake_queue() until half the device's TX
> > > queue is free, so we should get batching. However, I'm not sure that
> > > I can count on a fudge factor ensuring that there's enough space to
> > > handle everything skb_gso_segment() gives me -- is there any reliable
> > > way to get an upper bound on how many segments a given gso skb will
> > > use when it's segmented?
> >
> > Take a look at tg3.c. I use (gso_segs * 3) as the upper bound.
>
> Thanks for the pointer... I noticed that code, but could you tell me
> where the "* 3" comes from?
>
For each gso_seg, there will be a header and the payload may span 2
pages for 1500-byte packets. We always assume 1500-byte packets because
the buggy chips do not support jumbo frames.
next prev parent reply other threads:[~2007-05-15 21:17 UTC|newest]
Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-10 14:53 [RFC] New driver API to speed up small packets xmits Krishna Kumar
2007-05-10 15:08 ` Evgeniy Polyakov
2007-05-10 15:22 ` Krishna Kumar2
2007-05-10 15:48 ` Evgeniy Polyakov
2007-05-10 16:08 ` jamal
2007-05-10 17:19 ` Rick Jones
2007-05-10 18:07 ` Sridhar Samudrala
2007-05-10 19:43 ` Gagan Arneja
2007-05-10 20:11 ` jamal
2007-05-10 20:14 ` Rick Jones
2007-05-10 20:15 ` jamal
2007-05-10 20:15 ` Gagan Arneja
2007-05-10 20:21 ` jamal
2007-05-10 20:25 ` Gagan Arneja
2007-05-11 5:22 ` Krishna Kumar2
2007-05-11 11:27 ` jamal
2007-05-10 20:37 ` David Miller
2007-05-10 20:40 ` Gagan Arneja
2007-05-10 20:57 ` David Miller
2007-05-11 6:07 ` Krishna Kumar2
2007-05-11 5:21 ` Krishna Kumar2
2007-05-11 5:20 ` Krishna Kumar2
2007-05-11 5:35 ` Gagan Arneja
2007-05-11 5:43 ` Krishna Kumar2
2007-05-11 5:57 ` Gagan Arneja
2007-05-11 6:06 ` Krishna Kumar2
2007-05-11 6:29 ` Gagan Arneja
2007-05-11 6:52 ` Krishna Kumar2
2007-05-10 18:13 ` Vlad Yasevich
2007-05-10 18:20 ` Rick Jones
2007-05-10 18:32 ` Vlad Yasevich
2007-05-10 18:40 ` Rick Jones
2007-05-10 18:59 ` Ian McDonald
2007-05-10 19:21 ` Vlad Yasevich
2007-05-10 19:26 ` Ian McDonald
2007-05-10 20:32 ` David Miller
2007-05-10 20:49 ` Rick Jones
2007-05-10 21:02 ` David Miller
2007-05-10 21:14 ` Gagan Arneja
2007-05-11 2:28 ` Stephen Hemminger
2007-05-11 5:01 ` Gagan Arneja
2007-05-11 5:04 ` Krishna Kumar2
2007-05-11 9:01 ` Evgeniy Polyakov
2007-05-11 9:18 ` Krishna Kumar2
2007-05-11 9:32 ` Evgeniy Polyakov
2007-05-11 9:52 ` Krishna Kumar2
2007-05-11 9:56 ` Evgeniy Polyakov
2007-05-11 11:30 ` jamal
2007-05-11 11:53 ` Evgeniy Polyakov
2007-05-11 12:15 ` jamal
2007-05-10 21:27 ` David Stevens
2007-05-10 21:40 ` David Miller
2007-05-10 21:50 ` Gagan Arneja
2007-05-10 22:06 ` David Miller
2007-05-11 9:46 ` Krishna Kumar2
2007-05-10 21:41 ` Eric Dumazet
2007-05-10 22:09 ` Rick Jones
2007-05-10 21:45 ` Rick Jones
2007-05-10 21:53 ` David Stevens
2007-05-10 20:21 ` Roland Dreier
2007-05-11 7:30 ` Krishna Kumar2
2007-05-11 11:21 ` Roland Dreier
2007-05-11 9:05 ` Andi Kleen
2007-05-11 8:32 ` Krishna Kumar2
2007-05-11 9:37 ` Andi Kleen
2007-05-11 8:50 ` Krishna Kumar2
2007-05-11 11:16 ` Roland Dreier
2007-05-13 6:00 ` Andi Kleen
2007-05-15 16:25 ` Roland Dreier
2007-05-15 20:18 ` David Miller
2007-05-15 20:52 ` Roland Dreier
2007-05-15 21:48 ` Michael Chan
2007-05-15 21:08 ` Roland Dreier
2007-05-15 22:05 ` Michael Chan [this message]
2007-05-15 21:28 ` David Miller
2007-05-18 7:04 ` Michael Chan
-- strict thread matches above, loose matches on Subject: below --
2007-05-11 7:14 Krishna Kumar2
[not found] <OF0CAD6D87.DBE62968-ON872572DC.0073646A-882572DC.0073BEC2@us.ibm.com>
2007-05-15 21:17 ` Roland Dreier
[not found] ` <OFF5654BB8.74EC8DCB-ON872572DC.00752079-882572DC.00756B23@us.ibm.com>
2007-05-15 21:25 ` Roland Dreier
[not found] ` <OF21D475A2.5E5C88DE-ON872572DC.00763DE4-882572DC.00768A7E@us.ibm.com>
2007-05-15 21:38 ` David Miller
2007-05-15 21:32 ` David Miller
[not found] ` <OF6757F56D.EE5984FD-ON872572DC.0081026C-882572DC.00814B8F@us.ibm.com>
2007-05-15 23:36 ` David Miller
2007-05-21 7:56 ` Herbert Xu
[not found] ` <OF9ABCD08D.2CD1B193-ON872572E3.007A6FC1-882572E3.007ACE1A@us.ibm.com>
2007-05-22 22:36 ` David Miller
[not found] ` <OFCF3EB7F8.9740C0C7-ON872572E3.007DADF6-882572E3.007E0E7B@us.ibm.com>
2007-05-22 23:04 ` David Miller
2007-05-22 23:12 ` 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=1179266728.25622.46.camel@dell \
--to=mchan@broadcom.com \
--cc=ak@suse.de \
--cc=davem@davemloft.net \
--cc=krkumar2@in.ibm.com \
--cc=netdev@vger.kernel.org \
--cc=rdreier@cisco.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.