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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Networking overhead… vlan routing perhaps; 1) with either adding an extra network device hop and latency from a network device/router or 2) overburdened switch
handling the routing itself still introducing network latency. Latency is the storage and network i/o bandwidth killer.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I’m willing to bet two things:
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">1) changing your stripe size from 2 to 1 will make similar bandwidth results to the diagram 2 [54.3MB/s], even if the layout is as diagram 1 [separate nets].<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">2) If all your OSS/MDS and Clients nodes were in the same single vlan network…you’d see better performance than diagram’s 2 54.3MB/sec bandwidth throughput.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">So, drop classful subnets…go with cidr / supernetting networks to get the ip spaces you need and drop the extra routing latency.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Charles<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Courier New";color:#1F497D">--
<br>
===========================================<br>
Charles Hammitt<br>
Storage Systems Specialist<br>
ITS Research Computing @ <o:p></o:p></span></p>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Courier New";color:#1F497D">The University of North Carolina-CH<br>
<br>
===========================================<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> lustre-discuss-bounces@lists.lustre.org [mailto:lustre-discuss-bounces@lists.lustre.org]
<b>On Behalf Of </b>zhengfeng<br>
<b>Sent:</b> Thursday, March 15, 2012 12:11 AM<br>
<b>To:</b> lustre-discuss@lists.lustre.org<br>
<b>Subject:</b> [Lustre-discuss] Lustre read performance decay when OSSes are assigned in two different subnet<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:navy"> </span><span style="font-size:10.5pt;color:navy"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">Dear all,<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;color:black">We met</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">one problem about Lustre read performance decay when OSSes are assigned
in two different subnet.<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;color:black">Describing that in the following diagram:<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;color:black">diagram 1, OSS in different subnets:<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;color:black">Client (subnet 10.0.1.2)<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">Switch
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:96.0pt">
<span style="font-size:10.5pt;color:black">|</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |
<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:96.0pt">
<span style="font-size:10.5pt;color:black">|</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:96.0pt">
<span style="font-size:10.5pt;color:black">|</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:1.0in"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> OSS1</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">
OSS2<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:1.0in"><span style="font-size:10.5pt;color:black">(10.0.2.2)</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">(10.0.3.2)<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;color:black">For diagram 1, we made the CLient OSS1 and OSS2 in 3 different subnets. the switch</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">used</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">is
able forward</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">all packages.</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;color:black">Use dd cmd to test r/w performance<span lang="ZH-CN">，</span> write/rad data to/from</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">to</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">OSS1
and OSS2 at the same time:<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">test result:<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">[root@client</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">client]#</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">time</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">dd</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">if=test2</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">of=/dev/null</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">bs=1M</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">count=2000<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">2000+0</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">records</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">in<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">2000+0</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">records</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">out<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">2097152000</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">bytes</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">(2.1</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">GB)</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">copied,</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">53.5922</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">seconds,</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">39.1</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">MB/s<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black"><o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">real 0m53.796s<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">user 0m0.005s<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<i><span style="font-size:10.5pt;color:black">sys 0m2.914s<o:p></o:p></span></i></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
</div>
<div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;color:black">diagram 2, OSS in same subnet:<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;color:black">Client (subnet 10.0.1.2)<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:120.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:24.0pt">
<span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">Switch
<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:96.0pt">
<span style="font-size:10.5pt;color:black">|</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |
<o:p></o:p></span></p>
<div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:96.0pt">
<span style="font-size:10.5pt;color:black">|</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
</div>
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</div>
<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:96.0pt">
<span style="font-size:10.5pt;color:black">|</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> |<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:1.0in"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"> OSS1</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">
OSS2<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt;text-indent:1.0in"><span style="font-size:10.5pt;color:black">(10.0.2.2, 10.0.2.3, at same subnet)<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">for diagram 2, we assigned OSS1 and OSS2 at the same subnet, then test:<o:p></o:p></span></p>
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<div>
<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">test result:<o:p></o:p></span></p>
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<span style="font-size:10.5pt;color:black">[root@client219</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">client]#</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">time</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">dd</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">of=/dev/null</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">if=test1</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">bs=1M</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><i><span style="font-size:10.5pt;color:black">10000+0</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">records</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">in<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><i><span style="font-size:10.5pt;color:black">10000+0</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">records</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">out<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><i><span style="font-size:10.5pt;color:black">10485760000</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">bytes</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">(10</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">GB)</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">copied,</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">193.07</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">seconds,</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">54.3</span></i><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black">MB/s<o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black"><o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><i><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span></i><i><span style="font-size:10.5pt;color:black"><o:p></o:p></span></i></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">conclusion:<o:p></o:p></span></p>
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<span style="font-size:10.5pt;color:black">In different subnets, the OSS read performance is 39.1</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">MB/s, while OSS in<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">same subnet, the read performance is 54.3</span><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black">MB/s.
the performance decays so much.<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;color:black">Question:<o:p></o:p></span></p>
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<span style="font-size:10.5pt;color:black">Why using different subnets in lustre, the performance decayed?<o:p></o:p></span></p>
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<span style="font-size:10.5pt;color:black">Anyone had met such problems? Many thanks for your answers and advice.<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><b><i><span style="font-size:10.5pt;color:black">B.R.<o:p></o:p></span></i></b></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><b><i><span style="font-size:10.5pt;color:black">Feng<o:p></o:p></span></i></b></p>
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<p class="MsoNormal" style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.5pt;font-family:"Times New Roman","serif";color:black"> </span><span style="font-size:10.5pt;color:black"><o:p></o:p></span></p>
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