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<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Hallo
everybody.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I´m
dealing with some deadlocks related to MPI, maybe due to a high number of used resources/handles.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>The
deadlock I´m observing is not strictly related to MPI communication but to the
use in my program of some sockets. And it happens, or at least I have so
experienced, on a machine cluster with Window Server 2008, not, for instance,
on Window XP.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>I´m
getting deeply in the issue, but one hypothesis which comes to my mind is that
the number of “File/Handle” simultaneously opened by the mpiexec called process
is too high and maybe reach some threshold limits.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>In
detail I have seen in the process explorer (Sysinternals.com) that the number
of associated file handles “Devices\Afd” is already extremely high at the
beginning of the code execution. This is certainly due to the inheritance of
the handle property which is used in the CreateProcess function of mpiexec and
the associated demon smpd. Actually those handles are coming exactly from smpd.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Now
I wonder if this could be a reason why, when I´m trying to create a socket and
communicate data, I´m getting stuck. <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>As
said, the problem happened at the moment only with Window Server 2008. The
number of “Devices\Afd” is actually also high in the XP case (in the order of
100), but in the Window Server exceeds quickly 200/300.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Is
anyone aware of possible strategies or solutions or ideas to be checked??<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Suggestions
are really welcome.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>In
case you need some more details on my installation, do not hesitate to ask.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Thanks
a lot<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Eugenio<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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