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From: Brian W. Barrett (bbarrett_at_[hidden])
Date: 2007-02-13 21:37:05

On Feb 13, 2007, at 5:16 PM, Jeff Squyres wrote:

> On Feb 13, 2007, at 7:10 PM, George Bosilca wrote:
>> It's already in the 1.2 !!! I don't know much you care about
>> performance, but I do. This patch increase by 10% the latency. It
>> might be correct for the pathscale compiler, but it didn't look as a
>> huge requirement for all others compilers. A memory barrier for an
>> initialization and an unlock definitively looks like killing an ant
>> with a nuclear strike.
> Can we roll this back and find some other way?

Yes, we can.

It's not actually the memory barrier we need, it's the tell the
compiler to not do anything stupid because we expect memory to be
invalidated that we need. I'll commit a new, different fix tonight.


   Brian Barrett
   Open MPI Team, CCS-1
   Los Alamos National Laboratory