From: Andi Kleen <ak@linux.intel.com>
To: Dave Hansen <dave.hansen@intel.com>
Cc: paulmck@linux.vnet.ibm.com, LKML <linux-kernel@vger.kernel.org>,
Josh Triplett <josh@joshtriplett.org>,
"Chen, Tim C" <tim.c.chen@intel.com>,
Christoph Lameter <cl@linux.com>
Subject: Re: [bisected] pre-3.16 regression on open() scalability
Date: Tue, 17 Jun 2014 17:15:17 -0700 [thread overview]
Message-ID: <20140618001517.GL8178@tassilo.jf.intel.com> (raw)
In-Reply-To: <53A0CAE5.9000702@intel.com>
> It also ends up eating a new cacheline in a bunch of pretty hot paths.
> It would be nice to be able to keep the fast path part of this as at
> least read-only.
>
> Could we do something (functionally) like the attached patch? Instead
> of counting cond_resched() calls, we could just specify some future time
> by which we want have a quiescent state. We could even push the time to
> be something _just_ before we would have declared a stall.
I still think it's totally the wrong place. cond_resched() is in so
many fast paths (every lock, every allocation). It just doesn't
make sense to add non essential things like this to it.
I would be rather to just revert the original patch.
-Andi
next prev parent reply other threads:[~2014-06-18 0:15 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-13 20:04 Dave Hansen
2014-06-13 22:45 ` Paul E. McKenney
2014-06-13 23:35 ` Dave Hansen
2014-06-14 2:03 ` Paul E. McKenney
2014-06-17 23:10 ` Dave Hansen
2014-06-18 0:00 ` Josh Triplett
2014-06-18 0:15 ` Andi Kleen [this message]
2014-06-18 1:04 ` Paul E. McKenney
2014-06-18 2:27 ` Andi Kleen
2014-06-18 4:47 ` Paul E. McKenney
2014-06-18 12:40 ` Andi Kleen
2014-06-18 12:56 ` Paul E. McKenney
2014-06-18 14:29 ` Christoph Lameter
2014-06-18 0:18 ` Paul E. McKenney
2014-06-18 6:33 ` Dave Hansen
2014-06-18 12:58 ` Paul E. McKenney
2014-06-18 17:36 ` Dave Hansen
2014-06-18 20:30 ` Paul E. McKenney
2014-06-18 23:51 ` Paul E. McKenney
2014-06-19 1:42 ` Andi Kleen
2014-06-19 2:13 ` Paul E. McKenney
2014-06-19 2:29 ` Paul E. McKenney
2014-06-19 2:50 ` Mike Galbraith
2014-06-19 4:19 ` Paul E. McKenney
2014-06-19 3:38 ` Andi Kleen
2014-06-19 4:19 ` Paul E. McKenney
2014-06-19 5:24 ` Mike Galbraith
2014-06-19 18:14 ` Paul E. McKenney
2014-06-19 4:52 ` Eric Dumazet
2014-06-19 5:23 ` Paul E. McKenney
2014-06-19 14:42 ` Christoph Lameter
2014-06-19 18:09 ` Paul E. McKenney
2014-06-19 20:31 ` Christoph Lameter
2014-06-19 20:42 ` Paul E. McKenney
2014-06-19 20:50 ` Andi Kleen
2014-06-19 21:03 ` Paul E. McKenney
2014-06-19 21:13 ` Christoph Lameter
2014-06-19 21:16 ` Christoph Lameter
2014-06-19 21:32 ` josh
2014-06-19 23:07 ` Paul E. McKenney
2014-06-20 15:20 ` Christoph Lameter
2014-06-20 15:38 ` Paul E. McKenney
2014-06-20 16:07 ` Christoph Lameter
2014-06-20 16:30 ` Paul E. McKenney
2014-06-20 17:39 ` Dave Hansen
2014-06-20 18:15 ` Paul E. McKenney
2014-06-18 21:48 ` Paul E. McKenney
2014-06-18 22:03 ` Dave Hansen
2014-06-18 22:52 ` Paul E. McKenney
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=20140618001517.GL8178@tassilo.jf.intel.com \
--to=ak@linux.intel.com \
--cc=cl@linux.com \
--cc=dave.hansen@intel.com \
--cc=josh@joshtriplett.org \
--cc=linux-kernel@vger.kernel.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=tim.c.chen@intel.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