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<div>On 6/4/13 4:18 AM, "Jed Brown" <<a href="mailto:jedbrown@mcs.anl.gov">jedbrown@mcs.anl.gov</a>> wrote:</div>
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<div>Rolf Rabenseifner <<a href="mailto:rabenseifner@hlrs.de">rabenseifner@hlrs.de</a>> writes:</div>
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<div>I would say that the standard is not the right place to document this</div>
<div>sort of thing, but hopefully vendors and computing facilities will</div>
<div>document it prominently because it's an essential consideration for</div>
<div>MPI+MPI. It would be useful if someone would set up a resource</div>
<div>documenting the hoops one has to jump through on all major platforms.</div>
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<div>I think we're still waiting to figure out what those hoops are. For example, on platforms with XPMEM (Cray XT/XE/XC), the answer is have as many windows that are as big as you can allocate memory for. On most of the other platforms with Open MPI, it'll
be more along the lines of what you could allocate with POSIX shared memory interfaces, which is usually a high number of segments, but the total space is probably limited to a relatively small subset of the total memory (25%?).</div>
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<div>Brian</div>
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<div style="font-family: Tahoma; font-size: 13px; "><font size="2" face="Tahoma">--</font></div>
<div style="font-family: Tahoma; font-size: 13px; "><font size="2" face="tahoma"> Brian W. Barrett</font></div>
<div style="font-family: Tahoma; font-size: 13px; "><font size="2" face="tahoma"> Scalable System Software Group</font></div>
<div style="font-family: Tahoma; font-size: 13px; "><font size="2" face="tahoma"> Sandia National Laboratories</font></div>
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