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<p>Hallo Jaime,</p>
<p><br></p>
<p>Montag, 5. Mai 2008, meintest Du:</p>
<p><br></p>
<p><span class=rvts6>JP> Hello,</span></p>
<p><br></p>
<p><span class=rvts6>JP> Just a small question, does anybody has experience with many core</span></p>
<p><span class=rvts6>JP> (16) nodes and infiniband? Since we have some users that need</span></p>
<p><span class=rvts6>JP> shared memory but also we want to build a normal cluster for</span></p>
<p><span class=rvts6>JP> mpi apps, we think that this could be a solution. Let's say about</span></p>
<p><span class=rvts6>JP> 8 machines (96 processors) pus infiniband. Does it sound correct?</span></p>
<p><span class=rvts6>JP> I'm aware of the bottleneck that means having one ib interface for </span></p>
<p><span class=rvts6>JP> the mpi cores, is there any possibility of bonding?</span></p>
<p><br></p>
<p>i had another idea. Roughly one can say that a quad socket system is three times as expensive as a dual socket system -> so you spend a lot of money for "some users". Maybe it is worth thinking about using dual-socket machines and test if scaleMP gives you a good performance over two of them combined. I have no experience with that but maybe you can find that out...</p>
<p><br></p>
<p>For the interconnect it would be useful to know what and how your application is communicating. Big messages? Small messages? Complex operations? Maybe you can find out.</p>
<p><br></p>
<p>Cheers,</p>
<p>Jan</p>
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