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<p class="MsoNormal">Hi Fred,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We sometimes find a node will show that GPFS is active when running mmgetstate, but one of our GPFS filesystems, (such as our home or projects filesystems) are inaccessible to users, while the other GPFS-mounted filesystems behave as expected.
Our current node health checks don’t always detect this, especially when it’s for a resource-based mount that doesn’t impact the node but would impact jobs trying to run on the node.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If there is something native to GPFS that can detect this, all the better, but I’m simply unaware of how to do so.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Alex</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Senior Systems Administrator<br>
<br>
Research Computing Infrastructure<br>
Northwestern University Information Technology (NUIT)<br>
<br>
2020 Ridge Ave<br>
Evanston, IL 60208-4311<br>
<br>
O: (847) 491-2219<br>
M: (312) 887-1881<br>
www.it.northwestern.edu</p>
<p class="MsoNormal"><o:p> </o:p></p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> gpfsug-discuss-bounces@spectrumscale.org <gpfsug-discuss-bounces@spectrumscale.org> on behalf of Frederick Stock <stockf@us.ibm.com><br>
<b>Sent:</b> Friday, August 9, 2019 1:03:09 PM<br>
<b>To:</b> gpfsug-discuss@spectrumscale.org <gpfsug-discuss@spectrumscale.org><br>
<b>Cc:</b> gpfsug-discuss@spectrumscale.org <gpfsug-discuss@spectrumscale.org><br>
<b>Subject:</b> Re: [gpfsug-discuss] Checking for Stale File Handles</font>
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<div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:12pt">
<div dir="ltr">Are you able to explain why you want to check for stale file handles? Are you attempting to detect failures of some sort, and why do the existing mechanisms in GPFS not provide the functionality you require?</div>
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<div class="socmaildefaultfont" dir="ltr" style="font-family:Arial, Helvetica, sans-serif;font-size:10.5pt">
<div dir="ltr"><br>
<font size="2" face="Default Sans Serif,Verdana,Arial,Helvetica,sans-serif"><span style="font-size:1.143em;">Fred<br>
__________________________________________________<br>
Fred Stock | IBM Pittsburgh Lab | 720-430-8821<br>
stockf@us.ibm.com</span></font></div>
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<blockquote data-history-content-modified="1" dir="ltr" style="border-left:solid #aaaaaa 2px; margin-left:5px; padding-left:5px; direction:ltr; margin-right:0px">
----- Original message -----<br>
From: Alexander John Mamach <alex.mamach@northwestern.edu><br>
Sent by: gpfsug-discuss-bounces@spectrumscale.org<br>
To: "gpfsug-discuss@spectrumscale.org" <gpfsug-discuss@spectrumscale.org><br>
Cc:<br>
Subject: [EXTERNAL] [gpfsug-discuss] Checking for Stale File Handles<br>
Date: Fri, Aug 9, 2019 1:46 PM<br>
<br>
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<p style="margin: 0px;">Hi folks,</p>
<p style="margin: 0px;"><o:p> </o:p></p>
<p style="margin: 0px;">We’re currently investigating a way to check for stale file handles on the nodes across our cluster in a way that minimizes impact to the filesystem and performance.</p>
<p style="margin: 0px;"><o:p> </o:p></p>
<p style="margin: 0px;">Has anyone found a direct way of doing so? We considered a few methods, including simply attempting to ls a GPFS filesystem from each node, but that might have false positives, (detecting slowdowns as stale file handles), and could negatively
impact performance with hundreds of nodes doing this simultaneously.</p>
<p style="margin: 0px;"><o:p> </o:p></p>
<p style="margin: 0px;">Thanks,</p>
<p style="margin: 0px;"><o:p> </o:p></p>
<p style="margin: 0px;">Alex</p>
<p style="margin: 0px;"><o:p> </o:p></p>
<p style="margin: 0px;">Senior Systems Administrator<br>
<br>
Research Computing Infrastructure<br>
Northwestern University Information Technology (NUIT)<br>
<br>
2020 Ridge Ave<br>
Evanston, IL 60208-4311<br>
<br>
O: (847) 491-2219<br>
M: (312) 887-1881<br>
www.it.northwestern.edu</p>
<p style="margin: 0px;"><o:p> </o:p></p>
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