linux-kernel - Re: [PATCH 2/2] mutex: Apply adaptive spinning on mutex

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 25 Mar 2011 11:31:38 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Tejun Heo <tj@...nel.org>
Cc:	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Chris Mason <chris.mason@...cle.com>,
	linux-kernel@...r.kernel.org, linux-btrfs@...r.kernel.org
Subject: Re: [PATCH 2/2] mutex: Apply adaptive spinning on mutex_trylock()


* Tejun Heo <tj@...nel.org> wrote:

> Hello,
> 
> On Thu, Mar 24, 2011 at 10:41:51AM +0100, Tejun Heo wrote:
> >         USER   SYSTEM   SIRQ    CXTSW  THROUGHPUT
> >  SIMPLE 61107  354977    217  8099529  845.100 MB/sec
> >  SPIN   63140  364888    214  6840527  879.077 MB/sec
> > 
> > On various runs, the adaptive spinning trylock consistently posts
> > higher throughput.  The amount of difference varies but it outperforms
> > consistently.
> 
> I've been running more of these tests and am having doubts about the
> consistency.  It seems that, even on a fresh filesystem, some random
> initial condition seems to have persistent effect on the whole run.
> I'll run more tests and report back.

Ok, and there's the deadlock issue as well which Steve noticed.

I'll zap the patches from tip:core/urgent and lets do this via tip:core/locking 
with a .40 timeframe and plenty of time of testing.

Thanks,

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/