Patch to use fence instructions

Martin Nilsson martin at
Wed Sep 21 04:45:13 PDT 2005

John Baldwin wrote:
> This patch changes the atomic operations and bus space barriers to use the x86 
> fence instructions.  Please test, thanks!

What kind of performance improvements can we expect with this patch?
Is it worthwile to compare performance on dualcore Pentium D with 
sysbench before and after this patch? Does it affect threads & mutex 

Sysbench is a benchmark specially made to determine lowlevel performance 
important for MySQL and be found here:


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