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<p>Dear all!</p>
<p><br></p>
<p><br></p>
<p>I found this <span class=rvts4>http://mvapich.cse.ohio-state.edu/performance/mvapich2/opteron/MVAPICH2-opteron-gen2-DDR.shtml</span><span class=rvts6> as reference value for MPI-latency of Infiniband. I try to reproduce those numbers at the moment but i'm stuck with</span></p>
<p><span class=rvts6><br></span></p>
<p><span class=rvts6># OSU MPI Latency Test v3.0</span></p>
<p><span class=rvts6># Size Latency (us)</span></p>
<p><span class=rvts6>0 3.07</span></p>
<p><span class=rvts6>1 3.17</span></p>
<p><span class=rvts6>2 3.16</span></p>
<p><span class=rvts6>4 3.15</span></p>
<p><span class=rvts6>8 3.19</span></p>
<p><span class=rvts6><br></span></p>
<p><span class=rvts6>Equipment is two quadsocket Opteron Blades (Supermicro) with Mellanox Ex DDR cards. Single 24 port switch connects them.</span></p>
<p><span class=rvts6><br></span></p>
<p><span class=rvts6>Can anybody help with suggestions what i can do to lower the latency? </span></p>
<p> </p>
<p><br></p>
<p>Regards, Jan </p>
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