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Date: Sat, 02 Feb 2008 21:56:42 +0200
From: Alexander Motin <mav@FreeBSD.org>
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To: Peter Jeremy <peterjeremy@optushome.com.au>
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Cc: freebsd-hackers@freebsd.org, freebsd-performance@freebsd.org
Subject: Re: Memory allocation performance
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Peter Jeremy пишет:
> On Sat, Feb 02, 2008 at 11:31:31AM +0200, Alexander Motin wrote:
>> To check UMA dependency I have made a trivial one-element cache which in my 
>> test case allows to avoid two for four allocations per packet.
> 
> You should be able to implement this lockless using atomic(9).  I haven't
> verified it, but the following should work.

I have tried this, but man 9 atomic talks:

The atomic_readandclear() functions are not implemented for the types
``char'', ``short'', ``ptr'', ``8'', and ``16'' and do not have any 
variants with memory barriers at this time.

-- 
Alexander Motin