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Re: Dynamically allocated locks

In message <>,
Jason Thorpe writes:

>On Mar 24, 2008, at 10:10 AM, Matt Thomas wrote:
>> Yes.  One / cacheline size is a dramatic waste of space.  Some  
>> systems have
>> 128 bytes per cacheline.  On systems with small caches or UP systems  
>> it's
>> extremely expensive.
>Two independent locks in a single cache line is guaranteed to crease a  
>false-sharing situation.  It is best avoided, even if cache pressure  
>is the trade-off.

Even on a UP system?  In the kernel? Surely not.

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