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[PING][BZ #16549, #16410] Remove pthread_(cond)wait assembly implementations?
- From: OndÅej BÃlka <neleai at seznam dot cz>
- To: Roland McGrath <roland at hack dot frob dot com>
- Cc: libc-alpha at sourceware dot org
- Date: Wed, 19 Feb 2014 14:19:54 +0100
- Subject: [PING][BZ #16549, #16410] Remove pthread_(cond)wait assembly implementations?
- Authentication-results: sourceware.org; auth=none
- References: <20140211172324 dot GA31923 at domone dot podge> <20140211172720 dot 52ABB7445F at topped-with-meat dot com> <20140211184530 dot GB32451 at domone dot podge>
On Tue, Feb 11, 2014 at 07:45:30PM +0100, OndÅej BÃlka wrote:
> On Tue, Feb 11, 2014 at 09:27:20AM -0800, Roland McGrath wrote:
> > These were written in assembly to begin with because C versions did not
> > perform adequately. It's entirely possible the compiler has improved
> > enough to change that calculus. But actual performance analysis is
> > required.
>
> I used following benchmark for timedwait and deleting assembly
> implementation actually improves performance by around 5000 cycles.
>
As using C improves performance in this case could we proceed with
removing assembly?
> old one:
>
> cond wait spend time: 0.000067360
> cond wait spend time: 0.000064957
> cond wait spend time: 0.000055014
> cond wait spend time: 0.000063775
> cond wait spend time: 0.000064073
> cond wait spend time: 0.000063578
> cond wait spend time: 0.000063339
> cond wait spend time: 0.000064064
> cond wait spend time: 0.000063312
> cond wait spend time: 0.000063331
>
> new one:
>
> cond wait spend time: 0.000064140
> cond wait spend time: 0.000062096
> cond wait spend time: 0.000061748
> cond wait spend time: 0.000061601
> cond wait spend time: 0.000061581
> cond wait spend time: 0.000061620
> cond wait spend time: 0.000061725
> cond wait spend time: 0.000061611
> cond wait spend time: 0.000061601
> cond wait spend time: 0.000061591
>