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<div>My initial question is what are you measuring and where are you measuring it?</div>
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<div>There are many different layers of caching happening, possibly all at the same time. If you're benchmarking it's much better to figure out your max sustained read/write speeds than rely on peaks.</div>
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<div>-Ben</div>
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<span style="font-weight:bold">From: </span>lustre-discuss <<a href="mailto:lustre-discuss-bounces@lists.lustre.org">lustre-discuss-bounces@lists.lustre.org</a>> on behalf of "E.S. Rosenberg" <<a href="mailto:esr+lustre@mail.hebrew.edu">esr+lustre@mail.hebrew.edu</a>><br>
<span style="font-weight:bold">Date: </span>Monday, February 6, 2017 at 3:25 PM<br>
<span style="font-weight:bold">To: </span>"<a href="mailto:lustre-discuss@lists.lustre.org">lustre-discuss@lists.lustre.org</a>" <<a href="mailto:lustre-discuss@lists.lustre.org">lustre-discuss@lists.lustre.org</a>><br>
<span style="font-weight:bold">Subject: </span>[lustre-discuss] Traffic compression?<br>
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<div>We started closer monitoring of resources on our cluster and I noticed that there is sometimes a big discrepancy between the read traffic reported by Lustre and the incoming traffic reported by infiniband (which is the interace carrying the Lustre traffic).<br>
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Currently I have a 4.4GB peak on Lustre while Infiniband at the same time is showing just 1.4GB/s traffic (also there is a 2 minute difference between the 2 peaks)<br>
This is the summation of all the nodes (without the servers) in the cluster.<br>
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The stats are gathered using collectl at a 1 minute interval.<br>
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Thanks,<br>
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Eli<br>
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(There are also lots of stats that match 1:1 which makes me less sure what to make of this)<br>
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