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<DIV dir=ltr align=left><SPAN class=384274915-28052007><FONT face=Arial
color=#0000ff size=2>If it crashes at the first send/recv, can you take out
everything in the code after the first send/recv and see if it still crashes.
That will give you something smaller to debug.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=384274915-28052007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=384274915-28052007><FONT face=Arial
color=#0000ff size=2>Rajeev</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=384274915-28052007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> owner-mpich-discuss@mcs.anl.gov
[mailto:owner-mpich-discuss@mcs.anl.gov] <B>On Behalf Of </B>Christian
Zemlin<BR><B>Sent:</B> Monday, May 28, 2007 5:24 AM<BR><B>To:</B>
mpich-discuss@mcs.anl.gov<BR><B>Subject:</B> [MPICH] Simple MPI program
crashes randomly<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><FONT face=Arial size=2>The attached program ran literally thousands of
times on our old cluster, which has MPICH1 libraries, without any
problems.</FONT></DIV>
<DIV><FONT face=Arial size=2>It is simple in terms of MPI (just the minimum
MPI setup + a few Send and Recv commands), although it is fairly long because
it implements a complicated model of cardiac tissue.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>On our new cluster (with MPICH2) the program
crashes with segmentation faults either on the first MPI_Send/Recv or at the
end (MPI_Finalize). If you run it several times in a row, it seems to be
random which of the two occurs. I have checked carefully that the space
for the passed data has been allocated.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I would greatly appreciate if someone with more
MPI experience could have a look at the source code and give me his/her
opinion.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Best,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Christian</FONT></DIV></BLOCKQUOTE></BODY></HTML>