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Hi All,
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<div class="">Been reading man pages, docs, and Googling, and haven’t found a definitive answer to this question, so I knew exactly where to turn… ;-)</div>
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<div class="">I’m dealing with some slow I/O’s to certain storage arrays in our environments … like really, really slow I/O’s … here’s just one example from one of my NSD servers of a 10 second I/O:</div>
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<div class="">08:49:34.943186 W data 30:41615622144 2048 10115.192 srv dm-92 <client IP redacted></div>
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<div class="">So here’s my question … when mmdiag —iohist tells me that that I/O took slightly over 10 seconds, is that:</div>
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<div class="">1. The time from when the NSD server received the I/O request from the client until it shipped the data back onto the wire towards the client?</div>
<div class="">2. The time from when the client issued the I/O request until it received the data back from the NSD server?</div>
<div class="">3. Something else?</div>
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<div class="">I’m thinking it’s #1, but want to confirm. Which one it is has very obvious implications for our troubleshooting steps. Thanks in advance…</div>
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<div class="">Kevin</div>
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<div class="">Kevin Buterbaugh - Senior System Administrator</div>
<div class="">Vanderbilt University - Advanced Computing Center for Research and Education</div>
<div class=""><a href="mailto:Kevin.Buterbaugh@vanderbilt.edu" class="">Kevin.Buterbaugh@vanderbilt.edu</a> - (615)875-9633</div>
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