From: Eric Dumazet <dada1@cosmosbay•com>
To: Evgeniy Polyakov <zbr@ioremap•net>
Cc: Stephen Hemminger <shemminger@vyatta•com>,
Herbert Xu <herbert@gondor•apana.org.au>,
berrange@redhat•com, et-mgmt-tools@redhat•com,
davem@davemloft•net, netdev@vger•kernel.org
Subject: Re: virt-manager broken by bind(0) in net-next.
Date: Sat, 31 Jan 2009 11:17:15 +0100 [thread overview]
Message-ID: <4984252B.8080508@cosmosbay.com> (raw)
In-Reply-To: <20090131095640.GA29099@ioremap.net>
Evgeniy Polyakov a écrit :
> On Sat, Jan 31, 2009 at 10:49:00AM +0100, Eric Dumazet (dada1@cosmosbay•com) wrote:
>> It appears you are always right, I have nothing to say then.
>>
>> Stupid I am.
>>
>> I vote for plain revert of your initial patch, since you are anaware
>> of performance problems it introduces. Then, probably nobody cares
>> of my complaints, so dont worry.
>
> Eric, do not get it soo personally :) After all it is only a matter of
> how we enjoy the process and have fun with the development.
>
> Really, I appreciate your work and help, and likely this
> misunderstanding happened because of a bad mix of the original bug and
> this performance implication. Original bug has really nothing with what
> we discuss here. And while the performance problem with bound sockets
> creation may be visible, I did not observe it, while the idea
> implemented with this approach shows up clearly in the graph I posted.
> So I vote by both hands to further improve it by moving things around so
> that there would be no unneded cache flushes during update of this
> field.
>
OK OK, as I said, dont worry, it was not a strong feeling from me, only
a litle bit upset, thats all.
We only need to know if the *fix* is solving Stephen problem
About performance effects of careful variable placement and percpu counter
strategy you might consult as an example :
http://lkml.indiana.edu/hypermail/linux/kernel/0812.1/01624.html
Now, with these patches applied, try to see effect of your new bsockets field
on a network workload doing lot of socket bind()/unbind() calls...
With current kernels, you probably wont notice because of inode/dcache hot
cache lines, but it might change eventually...
next prev parent reply other threads:[~2009-01-31 10:17 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20090128212114.38be3e8c@extreme>
[not found] ` <20090129103544.GC22110@redhat.com>
2009-01-30 5:35 ` virt-manager broken by bind(0) in net-next Stephen Hemminger
2009-01-30 8:16 ` Evgeniy Polyakov
[not found] ` <20090130081600.GA2717-i6C2adt8DTjR7s880joybQ@public.gmane.org>
2009-01-30 10:27 ` Daniel P. Berrange
2009-01-30 11:21 ` Evgeniy Polyakov
2009-01-30 12:53 ` Herbert Xu
[not found] ` <20090130125337.GA7155-lOAM2aK0SrRLBo1qDEOMRrpzq4S04n8Q@public.gmane.org>
2009-01-30 17:57 ` Stephen Hemminger
2009-01-30 18:41 ` Eric Dumazet
2009-01-30 21:50 ` Evgeniy Polyakov
2009-01-30 22:30 ` Eric Dumazet
2009-01-30 22:51 ` Evgeniy Polyakov
[not found] ` <20090130225113.GA13977-i6C2adt8DTjR7s880joybQ@public.gmane.org>
2009-01-31 0:36 ` Stephen Hemminger
2009-01-31 8:35 ` Evgeniy Polyakov
2009-01-31 2:52 ` Stephen Hemminger
2009-01-31 8:37 ` Evgeniy Polyakov
2009-01-31 9:17 ` Eric Dumazet
2009-01-31 9:31 ` Evgeniy Polyakov
2009-01-31 9:49 ` Eric Dumazet
2009-01-31 9:56 ` Evgeniy Polyakov
2009-01-31 10:17 ` Eric Dumazet [this message]
2009-02-01 12:42 ` Evgeniy Polyakov
2009-02-01 16:12 ` Eric Dumazet
2009-02-01 17:40 ` Evgeniy Polyakov
2009-02-01 20:31 ` David Miller
[not found] ` <20090130215008.GB12210-i6C2adt8DTjR7s880joybQ@public.gmane.org>
2009-02-01 5:58 ` Stephen Hemminger
2009-02-01 9:07 ` David Miller
2009-02-01 12:44 ` Evgeniy Polyakov
[not found] ` <498349F7.4050300-fPLkHRcR87vqlBn2x/YWAg@public.gmane.org>
2009-02-01 5:29 ` Stephen Hemminger
2009-01-30 6:50 ` Stephen Hemminger
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=4984252B.8080508@cosmosbay.com \
--to=dada1@cosmosbay$(echo .)com \
--cc=berrange@redhat$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=et-mgmt-tools@redhat$(echo .)com \
--cc=herbert@gondor$(echo .)apana.org.au \
--cc=netdev@vger$(echo .)kernel.org \
--cc=shemminger@vyatta$(echo .)com \
--cc=zbr@ioremap$(echo .)net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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