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<P><FONT SIZE=2 FACE="Arial">Folks,</FONT>
<BR><FONT SIZE=2 FACE="Arial">Our IT staff is not particularly knowledgeable about parallel computing. Their current upgrade plan centers around quad/quad or dual/hex boxes which would have 16 or 12 cores respectively. I have no doubt that such a machine would run a parallel job efficiently. My question is how well can I harness multiple boxes together? </FONT></P>
<P><FONT SIZE=2 FACE="Arial">The applications are all CFD (FLUENT, GASP, STAR, VULCAN). I am talking to the various software vendors about this but would like some info from the programming community. </FONT></P>
<P><FONT SIZE=2 FACE="Arial">Assuming the same memory per core am I better off with</FONT>
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<P><FONT SIZE=2 FACE="Arial">High core count (12-16) boxes on a gigabit switch</FONT>
<BR><FONT SIZE=2 FACE="Arial">Lower core count (2 -4) boxes on an infiniband switch.</FONT>
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<P><FONT SIZE=2 FACE="Arial">I understand that if I configure mpich correctly it will use shared memory on the mutli-core multi-processor boxes. If I end up with the high core count boxes, should I spec the frontside bus (or whatever it is called now) as high as possible??</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I also have concerns that a single power supply failure takes out more cores, though perhaps that is not such a problem</FONT>
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<P><FONT SIZE=2 FACE="Arial">Any information is greatly appreciated</FONT>
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<P><FONT SIZE=2 FACE="Arial">Thanks</FONT>
<BR><FONT SIZE=2 FACE="Arial">Andy</FONT>
<BR><FONT SIZE=2 FACE="Arial">--------------------</FONT>
<BR><FONT FACE="Times New Roman">Andrew Robertson P.E.</FONT>
<BR><FONT FACE="Times New Roman">CFD Analyst</FONT>
<BR><FONT FACE="Times New Roman">GASL Operations</FONT>
<BR><FONT FACE="Times New Roman">Tactical Propulsion and Controls</FONT>
<BR><FONT FACE="Times New Roman">ATK</FONT>
<BR><FONT FACE="Times New Roman">77 Raynor Avenue</FONT>
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<BR><A HREF="file://www.atk.com"><U><FONT COLOR="#0000FF" FACE="Times New Roman">www.atk.com</FONT></U></A>
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<P><FONT FACE="Times New Roman">!! Knowledge and Thoroughness Baby !!</FONT>
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