madhave i sent it to the entire beowulf mailing list. if you don't want to receive emails i recommend you unsubscribe from the list.<br><br><div class="gmail_quote">On Wed, Apr 22, 2009 at 8:55 AM, Madhav A <span dir="ltr"><<a href="mailto:madhav.appana@gmail.com">madhav.appana@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div>Plz don't send mail to me.</div>
<div>Plzzzzzzzzzzzzzzzzzzzzz dear</div>
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<div>Regards,</div>
<div>Madhav.A<font color="#888888"><br><br></font></div><div><div></div><div class="h5">
<div class="gmail_quote">On Wed, Apr 22, 2009 at 12:19 PM, Jonathan Aquilina <span dir="ltr"><<a href="mailto:eagles051387@gmail.com" target="_blank">eagles051387@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="padding-left:1ex;margin:0px 0px 0px 0.8ex;border-left:#ccc 1px solid">in regards to the models you run couldnt you wait until your about to leave for the day and let it run over night? to be honest i dont have much of a need for clustering at the moment. the only thing i can really run on this windows monster is boinc projects which i do. also gus doesnt the amount of cache play a role in regards to be able to working on the machine while crunching numbers, wont it keep swapping, etc to a minimum?<br>
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<div class="gmail_quote">On Wed, Apr 22, 2009 at 12:36 AM, Gus Correa <span dir="ltr"><<a href="mailto:gus@ldeo.columbia.edu" target="_blank">gus@ldeo.columbia.edu</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="padding-left:1ex;margin:0px 0px 0px 0.8ex;border-left:#ccc 1px solid">
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<div>Glen Beane wrote:<br>
<blockquote class="gmail_quote" style="padding-left:1ex;margin:0px 0px 0px 0.8ex;border-left:#ccc 1px solid"><br><br><br>On 4/21/09 3:46 PM, "Jonathan Aquilina" <<a href="mailto:eagles051387@gmail.com" target="_blank">eagles051387@gmail.com</a>> wrote:<br>
<br> is it possible to have a single multicored machine as a cluster?<br><br><br><br>That wouldn’t exactly be a cluster, would it? But you can certainly run a lot of the software associated with Beowulf clusters: a batch system (TORQUE, SGE, etc), MPI, ... so in practice you can use your 8 core workstation just like you would a cluster.<br>
<br><br>-- <br>Glen L. Beane<br>Software Engineer<br>The Jackson Laboratory<br>Phone (207) 288-6153<br><br><br></blockquote><br></div></div>Hi Jonathan, Glen, list<br><br>Along the lines that Glen pointed out,<br>I setup a dual-socket dual-core workstation here with OpenMPI<br>
and MPICH2, plus Torque, to run some of our atmosphere modeling code<br>in batch mode.<br>It is not really a cluster, but a workstation<br>with some software characteristic of a cluster.<br><br>We tend to have long series of atmospheric model runs, where<br>
each one-year simulation restarts from the previous state where<br>the last run stopped.<br>Each run can take, say, half a day to complete,<br>and the whole series may take a week to a month to finish.<br>Queuing the jobs up on Torque/PBS,<br>
and forgetting about them until the whole series is done is<br>very convenient.<br><br>This setup works fine as long as the workstation is relatively idle.<br>However, if/when the owner decides to run heavy data analysis<br>
Matlab scripts interactively while the MPI jobs are running,<br>then we get to memory contention, swapping, and all those bad things<br>that kill performance and may even break MPI jobs.<br>This "time shared" interactive activity, that is typically absent in cluster nodes, is germane to workstations.<br>
<br>Fortunately, I could convince the workstation owner (who also wants<br>the output of the atmospheric model runs) to do heavy interactive<br>use only when there aren't jobs on the Torque queue.<br>Or to suspend the job queue, wait for running jobs to complete,<br>
work interactively, then restart the queue.<br><br>You can think of other heavy interactive use (e.g. streaming video)<br>that can produce the same negative impact on MPI jobs,<br>and you may need to adopt a similar<br>policy to avoid conflict between interactive and batch use<br>
in your workstation, if you set it up "as a cluster".<br><br>My two cents.<br><font color="#888888"><br>Gus Correa<br>---------------------------------------------------------------------<br>Gustavo Correa<br>Lamont-Doherty Earth Observatory - Columbia University<br>
Palisades, NY, 10964-8000 - USA<br>---------------------------------------------------------------------</font>
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</div></div></blockquote></div><br><br clear="all"><br>-- <br><font color="#888888">Jonathan Aquilina<br></font><br>_______________________________________________<br>Beowulf mailing list, <a href="mailto:Beowulf@beowulf.org" target="_blank">Beowulf@beowulf.org</a> sponsored by Penguin Computing<br>
To change your subscription (digest mode or unsubscribe) visit <a href="http://www.beowulf.org/mailman/listinfo/beowulf" target="_blank">http://www.beowulf.org/mailman/listinfo/beowulf</a><br><br></blockquote></div><br>
</div></div></blockquote></div><br><br clear="all"><br>-- <br>Jonathan Aquilina<br>