netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>, David Miller <davem@davemloft.net>,
	wenji@fnal.gov, akpm@osdl.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [patch 1/4] - Potential performance bottleneck for Linxu TCP
Date: Thu, 30 Nov 2006 13:22:06 +0300	[thread overview]
Message-ID: <20061130102205.GA20654@2ka.mipt.ru> (raw)
In-Reply-To: <456EAD6E.6040709@yahoo.com.au>

On Thu, Nov 30, 2006 at 09:07:42PM +1100, Nick Piggin (nickpiggin@yahoo.com.au) wrote:
> >Doesn't the provided solution is just a in-kernel variant of the
> >SCHED_FIFO set from userspace? Why kernel should be able to mark some
> >users as having higher priority?
> >What if workload of the system is targeted to not the maximum TCP
> >performance, but maximum other-task performance, which will be broken
> >with provided patch.
> 
> David's line of thinking for a solution sounds better to me. This patch
> does not prevent the process from being preempted (for potentially a long
> time), by any means.

It steals timeslices from other processes to complete tcp_recvmsg()
task, and only when it does it for too long, it will be preempted.
Processing backlog queue on behalf of need_resched() will break fairness
too - processing itself can take a lot of time, so process can be
scheduled away in that part too.

> -- 
> SUSE Labs, Novell Inc.
> Send instant messages to your online friends http://au.messenger.yahoo.com 

-- 
	Evgeniy Polyakov

  reply	other threads:[~2006-11-30 10:22 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-11-30  1:56 [patch 1/4] - Potential performance bottleneck for Linxu TCP Wenji Wu
2006-11-30  2:19 ` David Miller
2006-11-30  6:17   ` Ingo Molnar
2006-11-30  6:30     ` David Miller
2006-11-30  6:47       ` Ingo Molnar
2006-11-30  7:12         ` David Miller
2006-11-30  7:35           ` Ingo Molnar
2006-11-30  9:52             ` Evgeniy Polyakov
2006-11-30 10:07               ` Nick Piggin
2006-11-30 10:22                 ` Evgeniy Polyakov [this message]
2006-11-30 10:32                   ` Ingo Molnar
2006-11-30 17:04                     ` Wenji Wu
2006-11-30 20:20                       ` Ingo Molnar
2006-11-30 20:58                         ` Wenji Wu
2006-11-30 20:22                     ` David Miller
2006-11-30 20:30                       ` Ingo Molnar
2006-11-30 20:38                         ` David Miller
2006-11-30 20:49                           ` Ingo Molnar
2006-11-30 20:54                             ` Ingo Molnar
2006-11-30 20:55                             ` David Miller
2006-11-30 20:14                   ` David Miller
2006-11-30 20:42                     ` Wenji Wu
2006-12-01  9:53                     ` Evgeniy Polyakov
2006-12-01 23:18                       ` David Miller
2006-11-30  6:56       ` Ingo Molnar
2006-11-30 16:08   ` Wenji Wu
2006-11-30 20:06     ` David Miller
2006-11-30  9:33 ` Christoph Hellwig
2006-11-30 16:51   ` Lee Revell
  -- strict thread matches above, loose matches on Subject: below --
2006-11-30  2:02 Wenji Wu
2006-11-30  6:19 ` Ingo Molnar
2006-11-29 23:27 [Changelog] " Wenji Wu
2006-11-29 23:28 ` [patch 1/4] " Wenji Wu
2006-11-30  0:53   ` David Miller
2006-11-30  1:08     ` Andrew Morton
2006-11-30  1:13       ` David Miller
2006-11-30  6:04       ` Mike Galbraith

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=20061130102205.GA20654@2ka.mipt.ru \
    --to=johnpol@2ka.mipt.ru \
    --cc=akpm@osdl.org \
    --cc=davem@davemloft.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=netdev@vger.kernel.org \
    --cc=nickpiggin@yahoo.com.au \
    --cc=wenji@fnal.gov \
    /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).