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From: Hubertus Franke <frankeh@watson.ibm.com>
Reply-To: frankeh@watson.ibm.com
Organization: IBM Research
To: Alan Cox <alan@lxorguk.ukuu.org.uk>,
        torvalds@transmeta.com (Linus Torvalds)
Subject: Re: [PATCH] Futexes IV (Fast Lightweight Userspace Semaphores)
Date: Fri, 8 Mar 2002 17:55:20 -0500
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Cc: rusty@rustcorp.com.au (Rusty Russell), linux-kernel@vger.kernel.org
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On Friday 08 March 2002 03:40 pm, Alan Cox wrote:
> > So I would suggest making the size (and thus alignment check) of locks at
> > least 8 bytes (and preferably 16). That makes it slightly harder to put
> > locks on the stack, but gcc does support stack alignment, even if the
> > code sucks right now.
>
> Can we go to cache line alignment - for an array of locks thats clearly
> advantageous

NO and let me explain.

I would to be able to integrate the lock with the data.
This is much more cache friendly then putting the lock on a different 
cacheline.

If you want an array you need to pad each element. 
That's easy enough to do....
Can't shrink a datastructure on the other hand :-)

-- 
-- Hubertus Franke  (frankeh@watson.ibm.com)
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