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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>Bonding (or multi-rail) does not make sense with "standard IB" in PCIe x8 since the PCIe connection limits the transfer rate of a single IB-Link already. </p>
<p><br></p>
<p>My hint would be to go for Infinipath from QLogic or the new ConnectX from Mellanox since message rate is probably your limiting factor and those technologies have a huge advantage over standard Infiniband SDR/DDR. </p>
<p><br></p>
<p>Infinipath and ConnectX are available as DDR Infiniband and provide a bandwidth of more than 1800 MB/s.</p>
<p><br></p>
<p>Cheers, Jan </p>
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