From: Nick Piggin <nickpiggin@yahoo.com.au>
To: Eric Dumazet <dada1@cosmosbay.com>
Cc: Andrea Arcangeli <andrea@suse.de>,
Anton Blanchard <anton@samba.org>, Rik van Riel <riel@redhat.com>,
Lorenzo Allegrucci <l_allegrucci@yahoo.it>,
linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
Suparna Bhattacharya <suparna@in.ibm.com>,
Jens Axboe <jens.axboe@oracle.com>
Subject: Re: SMP performance degradation with sysbench
Date: Tue, 13 Mar 2007 22:56:35 +1100 [thread overview]
Message-ID: <45F69173.3050202@yahoo.com.au> (raw)
In-Reply-To: <200703131240.47785.dada1@cosmosbay.com>
Eric Dumazet wrote:
> On Tuesday 13 March 2007 12:12, Nick Piggin wrote:
>
>>I guess googlemalloc (tcmalloc?) isn't suitable for a general purpose
>>glibc allocator. But I wonder if there are other improvements that glibc
>>can do here?
>
>
> I cooked a patch some time ago to speedup threaded apps and got no feedback.
Well that doesn't help in this case. I tested and the mmap_sem contention
is not an issue.
> http://lkml.org/lkml/2006/8/9/26
>
> Maybe we have to wait for 32 core cpu before thinking of cache line
> bouncings...
The idea is a good one, and I was half way through implementing similar
myself at one point (some java apps hit this badly).
It is just horribly sad that futexes are supposed to implement a
_scalable_ thread synchronisation mechanism, whilst fundamentally
relying on an mm-wide lock to operate.
I don't like your interface, but then again, the futex interface isn't
exactly pretty anyway.
You should resubmit the patch, and get the glibc guys to use it.
--
SUSE Labs, Novell Inc.
Send instant messages to your online friends http://au.messenger.yahoo.com
next prev parent reply other threads:[~2007-03-13 11:56 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-02-25 17:44 SMP performance degradation with sysbench Lorenzo Allegrucci
2007-02-25 23:46 ` Rik van Riel
2007-02-26 13:36 ` Nick Piggin
2007-02-26 13:41 ` Nick Piggin
2007-02-26 22:04 ` Pete Harlan
2007-02-26 22:36 ` Dave Jones
2007-02-27 0:32 ` Hiro Yoshioka
2007-02-27 0:43 ` Rik van Riel
2007-02-27 4:03 ` Hiro Yoshioka
2007-02-27 4:31 ` Rik van Riel
2007-02-27 8:14 ` J.A. Magallón
2007-02-27 14:02 ` Rik van Riel
2007-02-27 14:56 ` Paulo Marques
2007-02-27 20:40 ` Nish Aravamudan
2007-02-28 2:21 ` Bill Davidsen
2007-02-28 2:52 ` Nish Aravamudan
2007-03-01 0:20 ` Nish Aravamudan
2007-02-27 19:05 ` Lorenzo Allegrucci
2007-03-01 16:57 ` Lorenzo Allegrucci
2007-02-28 1:27 ` Nish Aravamudan
2007-02-28 2:22 ` Nick Piggin
2007-02-28 2:51 ` Nish Aravamudan
2007-03-12 22:00 ` Anton Blanchard
2007-03-13 5:11 ` Nick Piggin
2007-03-13 9:45 ` Andrea Arcangeli
2007-03-13 10:06 ` Nick Piggin
2007-03-13 10:31 ` Andrea Arcangeli
2007-03-13 10:37 ` Nick Piggin
2007-03-13 10:57 ` Andrea Arcangeli
2007-03-13 11:12 ` Nick Piggin
2007-03-13 11:40 ` Eric Dumazet
2007-03-13 11:56 ` Nick Piggin [this message]
2007-03-13 11:42 ` Andrea Arcangeli
2007-03-13 12:02 ` Eric Dumazet
2007-03-13 12:27 ` Jakub Jelinek
2007-03-13 12:08 ` Nick Piggin
2007-03-14 23:33 ` Siddha, Suresh B
2007-03-20 2:29 ` Zhang, Yanmin
2007-04-02 2:59 ` Zhang, Yanmin
2007-03-13 6:00 ` Eric Dumazet
2007-03-14 0:36 ` Nish Aravamudan
2007-03-14 1:00 ` Eric Dumazet
2007-03-14 1:09 ` Nish Aravamudan
[not found] <fa.V3M3ZgXL+lFlIyhx43YxCU/JFUk@ifi.uio.no>
[not found] ` <fa.ciL5lzdfskdJHJPgn+UVCHt/9EM@ifi.uio.no>
[not found] ` <fa.2ABbHhyCbp3Fx7hSE/Gr0SuzFvw@ifi.uio.no>
[not found] ` <fa.oaZk6Aiqd8gyZNsj7+m+w9MibhU@ifi.uio.no>
[not found] ` <fa.RjX9Y4ckjRCle5L+uWNdd0snOio@ifi.uio.no>
[not found] ` <fa.XocsudxlGplKh0kloTtA0juPwtA@ifi.uio.no>
2007-02-28 0:20 ` Robert Hancock
2007-02-28 1:32 ` Hiro Yoshioka
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=45F69173.3050202@yahoo.com.au \
--to=nickpiggin@yahoo.com.au \
--cc=andrea@suse.de \
--cc=anton@samba.org \
--cc=dada1@cosmosbay.com \
--cc=jens.axboe@oracle.com \
--cc=l_allegrucci@yahoo.it \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=riel@redhat.com \
--cc=suparna@in.ibm.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.