From: Corey Minyard <minyard@acm.org>
To: Eric Dumazet <dada1@cosmosbay.com>
Cc: Benny Amorsen <benny+usenet@amorsen.dk>,
David Miller <davem@davemloft.net>,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
shemminger@vyatta.com, paulmck@linux.vnet.ibm.com
Subject: Re: [PATCH 3/3] Convert the UDP hash lock to RCU
Date: Tue, 07 Oct 2008 11:43:04 -0500 [thread overview]
Message-ID: <48EB9198.1090605@acm.org> (raw)
In-Reply-To: <48EB5D28.7000503@cosmosbay.com>
Eric Dumazet wrote:
>
> (2 weeks ago, Corey mentioned a 10x increase on UDP throughput on a
> 16-way machine,
> that sounds promising)
Just to be clear, that was 10x with preempt RT, which converts rwlocks
into PI mutexes. So 16 processors going for the same lock is pretty ugly.
Under heavy loads there is also a writer starvation problem, I believe
in non-RT. You can't actually create or destroy a UDP socket when the
load is high because there's always a reader holding the lock. RCU also
solves that problem.
-corey
next prev parent reply other threads:[~2008-10-07 16:43 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-10-06 18:50 Corey Minyard
2008-10-06 21:22 ` Eric Dumazet
2008-10-06 21:40 ` David Miller
2008-10-06 23:08 ` Corey Minyard
2008-10-07 8:37 ` Evgeniy Polyakov
2008-10-07 14:16 ` Christoph Lameter
2008-10-07 14:29 ` Evgeniy Polyakov
2008-10-07 14:38 ` Christoph Lameter
2008-10-07 14:33 ` Paul E. McKenney
2008-10-07 14:45 ` Christoph Lameter
2008-10-07 15:07 ` Eric Dumazet
2008-10-07 15:07 ` Paul E. McKenney
2008-10-07 5:24 ` Eric Dumazet
2008-10-07 8:54 ` Benny Amorsen
2008-10-07 12:59 ` Eric Dumazet
2008-10-07 14:07 ` Stephen Hemminger
2008-10-07 20:55 ` David Miller
2008-10-07 21:20 ` Stephen Hemminger
2008-10-08 13:55 ` Eric Dumazet
2008-10-08 18:45 ` David Miller
2008-10-07 16:43 ` Corey Minyard [this message]
2008-10-07 18:26 ` David Miller
2008-10-08 8:35 ` Eric Dumazet
2008-10-08 16:38 ` David Miller
2008-10-07 8:31 ` Peter Zijlstra
2008-10-07 14:36 ` Paul E. McKenney
2008-10-07 18:29 ` David Miller
2008-10-06 22:07 ` Corey Minyard
2008-10-07 8:17 ` Peter Zijlstra
2008-10-07 9:24 ` Eric Dumazet
2008-10-07 14:15 ` Christoph Lameter
2008-10-07 14:38 ` Paul E. McKenney
2008-10-07 14:50 ` Eric Dumazet
2008-10-07 15:05 ` Paul E. McKenney
2008-10-07 15:09 ` Peter Zijlstra
2008-10-07 15:23 ` Christoph Lameter
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=48EB9198.1090605@acm.org \
--to=minyard@acm.org \
--cc=benny+usenet@amorsen.dk \
--cc=dada1@cosmosbay.com \
--cc=davem@davemloft.net \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=shemminger@vyatta.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome