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Hi.<br>I think you have a bit confusion here ..!<br>-np $Nprocess <br>Nprocess means number of processes that work in parallel ,not the number of cores ...!<br>In Addition ..MPI works sequentially on one machine so the load will increase ...<br><br>Zain Elabedin <br><br><hr id="stopSpelling">Date: Fri, 4 Dec 2009 17:02:28 +0800<br>From: ustcliao@gmail.com<br>To: mpich-discuss@mcs.anl.gov<br>Subject: [mpich-discuss] MPI how to support the smp machine?<br><br>I am runing the HPL ( A Portable Implementation of the High-Performance Linpack
Benchmark for Distributed-Memory Computers) to do linpcke test.<br><br>I use the Atlas to as blas lib.<br><br>My machine has one cpu with four core.<br><br>I run the mpirun -np 1 ./xhlp the Gflops is 0.4 (one core to run)<br>
<br>but I run the mpirun -np 2 ./xhlp the Gflops is 0.04 (two core to run)<br><br>why is the two core is slower.<br><br> <br /><hr />Keep your friends updated— <a href='http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/social-network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_5:092010' target='_new'>even when you’re not signed in.</a></body>
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