<html><head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">
<div class="">Hi Daniel,</div>
<div class=""><br class="">
</div>
<div class="">We are actually working on this at the moment. There is a ticket to describe the status of the work: <a href="https://trac.mpich.org/projects/mpich/ticket/79" class="">https://trac.mpich.org/projects/mpich/ticket/79</a>. Despite the appearance,
there is work planned here. Currently, this is slated for MPICH 3.3 in 2016. It’s possible that it could show up earlier in the nightlies, but there’s no guarantees.</div>
<div class=""><br class="">
</div>
<div class="">Thanks,</div>
<div class="">Wesley</div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Dec 9, 2014, at 1:17 PM, Daniel Ibanez <<a href="mailto:dan.a.ibanez@gmail.com" class="">dan.a.ibanez@gmail.com</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div dir="ltr" class="">Hello,
<div class=""><br class="">
</div>
<div class="">I have noticed that simple things like MPI_Barrier</div>
<div class="">will raise my CPU usage to near 100% while waiting,</div>
<div class="">and read in past emails and the FAQ that this is due</div>
<div class="">to busy polling in Nemesis.</div>
<div class="">As far as I can tell, the one solution usually offered</div>
<div class="">to reduce this CPU usage</div>
<div class="">is reconfiguring with sockets instead of Nemesis.</div>
<div class="">I would also like to use the MPI_THREAD_MULTIPLE</div>
<div class="">feature, but I read that the socket channels</div>
<div class="">don't support it, and it would be annoying to</div>
<div class="">have to recompile MPICH to get one benefit or the other.</div>
<div class=""><br class="">
</div>
<div class="">I was just wondering if recent advancements invalidated</div>
<div class="">some of the above and officially ask what the options are</div>
<div class="">for reducing the CPU usage of MPICH during barriers.</div>
<div class=""><br class="">
</div>
<div class="">Thank you,</div>
</div>
_______________________________________________<br class="">
discuss mailing list <a href="mailto:discuss@mpich.org" class="">discuss@mpich.org</a><br class="">
To manage subscription options or unsubscribe:<br class="">
<a href="https://lists.mpich.org/mailman/listinfo/discuss" class="">https://lists.mpich.org/mailman/listinfo/discuss</a></div>
</blockquote>
</div>
<br class="">
</body>
</html>