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Date: Wed, 28 Apr 2010 23:39:59 -0300
Message-ID: <s2q32d987d51004281939pc251a095tf1d2c481a93e00be@mail.gmail.com>
From: "Federico G. Benavento" <benavento@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: Re: [9fans] LOCK XADD for i386 incref/decref
Topicbox-Message-UUID: 1212da22-ead6-11e9-9d60-3106f5b1d025

sorry, but why in the compiler and not as a library function like in libthread?

http://plan9.bell-labs.com/sources/plan9/sys/src/libthread/xinc386.s

On Wed, Apr 28, 2010 at 4:16 PM, Venkatesh Srinivas
<me@endeavour.zapto.org> wrote:
> Hi,
>
> A few months ago, I added a patch to inferno-npe to use LOCK XADD
> instead of the current lock/add/unlock sequence for incref and decref:
> (http://code.google.com/p/inferno-npe/source/detail?r=b83540e1e77e62a19cbd21d2eb54d43d338716a5
> and http://code.google.com/p/inferno-npe/source/detail?r=82f13e6755218ecb7dec0f1392b2eb8bfe0bb2c7).
> On a 2.66 GHz Core 2 Duo, we noticed a full 14% reduction in runtime
> (9.6s vs 11.2s) of the thread-ring test. Similar performance gains
> were noticed on a Core i7 machine, but I no longer have the numbers
> handy.
>
> Perhaps this change is interesting for Plan 9...
>
> -- vs
>
>



--
Federico G. Benavento