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Another, very important note on PC GAMESS/Firefly running on Core i7/Xeon 5500/Xeon 3500 (Nehalem core) processors

Alex Granovsky
gran@classic.chem.msu.su


Dear Firefly users,

the p4stuff.dll/p4stuff.ex dynamic/shared library which can be
optionally used by the PC GAMESS/Firefly contains several
32-bit matrix multiplication routines (dgemm) taken from Intel's MKL.

Several days ago we found two critical bugs in Intel's
implementation of 32-bit dgemm routines which are used on
Penryn and Nehalem-core processors. The bugs manifest themself
only for large matrices and thus are "hidden".

These bugs can potentially affect PC GAMESS/Firefly using
its default settings and running on Nehalem-core processors
under 32-bit Windows, under 32-bit or 64-bit Linux, and Mac OS X.

The solution is to disable use of externally stored dgemm
running Firefly on Nehalem core processors:

 $smp call64=1 load=0 $end

We are working with Intel and hope to provide the replacement
p4stuff library based on the fixed MKL code within a couple of weeks.

Regards,
Alex Granovsky





[ This message was edited on Thu May 21 '09 at 9:23pm by the author ]


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