<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252">
</head>
<body>
<div dir="ltr" text-align="left">
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
Thanks for the reply, Tim.</div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
<span style="font-size: 1em;"><br>
</span></div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
<span style="font-size: 1em;">Are there any tools I can use to see if that is the cause?</span></div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
<span style="font-size: 1em;"><br>
</span></div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
Could any tuning possibly help the situation?</div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
<br>
</div>
<div style="color: rgb(33, 33, 33); background-color: rgb(255, 255, 255); text-align: left;" dir="ltr">
Thanks</div>
<div id="ms-outlook-mobile-signature">
<div><br>
</div>
</div>
<div id="id-af22d8ad-1108-4712-b1bd-3fb6590b05bf" class="ms-outlook-mobile-reference-message">
<div style="font-family: sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"><br>
</div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg"><strong>From:</strong> Carlson, Timothy S <Timothy.Carlson@pnnl.gov><br>
<strong>Sent:</strong> Monday, 28 October 2019, 17:24<br>
<strong>To:</strong> Louis Allen; lustre-discuss@lists.lustre.org<br>
<strong>Subject:</strong> RE: Lustre Timeouts/Filesystem Hanging<br>
</div>
<br>
<meta content="text/html; charset=Windows-1252">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style>
<!--
@font-face
{font-family:"Cambria Math"}
@font-face
{font-family:Calibri}
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif}
a:link, span.MsoHyperlink
{color:#0563C1;
text-decoration:underline}
a:visited, span.MsoHyperlinkFollowed
{color:#954F72;
text-decoration:underline}
p.msonormal0, li.msonormal0, div.msonormal0
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif}
span.EmailStyle19
{font-family:"Calibri",sans-serif;
color:windowtext}
.MsoChpDefault
{font-size:10.0pt}
@page WordSection1
{margin:1.0in 1.0in 1.0in 1.0in}
div.WordSection1
{}
-->
</style>
<div class="WordSection1">
<p class="MsoNormal">In my experience, this is almost always related to some code doing really bad I/O. Let’s say you have a 1000 rank MPI code doing open/read 4k/close on a few specific files on that OST. That will make for a bad day.</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">The other place you can see this, and this isn’t your case, is when ZFS refuses to give up on a disk that is failing and your overall I/O suffers from ZFS continuing to try to read from a disk that it should just kick out</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Tim</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"> </p>
<div>
<div style="border:none; border-top:solid #E1E1E1 1.0pt; padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b>From:</b> lustre-discuss <lustre-discuss-bounces@lists.lustre.org>
<b>On Behalf Of </b>Louis Allen<br>
<b>Sent:</b> Monday, October 28, 2019 10:16 AM<br>
<b>To:</b> lustre-discuss@lists.lustre.org<br>
<b>Subject:</b> [lustre-discuss] Lustre Timeouts/Filesystem Hanging</p>
</div>
</div>
<p class="MsoNormal"> </p>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Hello,</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Lustre (2.12) seem to be hanging quite frequently (5+ times a day) for us and one of the OSS servers (out of 4) is reporting an extremely high load average (150+) but the CPU usage of that server
is actually very low - so it must be related to something else - possibly CPU_IO_WAIT.</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">The OSS server we are seeing the high load averages we can also see multiple LustreError messages in /var/log/messages:</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: LNet: Service thread pid 2403 was inactive for 200.08s. The thread might be hung, or it might only be slow and will resume later. Dumping the stack trace
for debugging purposes:</span></p>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: LNet: Skipped 4 previous similar messages</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: Pid: 2403, comm: ll_ost00_068 3.10.0-957.10.1.el7_lustre.x86_64 #1 SMP Sun May 26 21:48:35 UTC 2019</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: Call Trace:</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc03747c5>] jbd2_log_wait_commit+0xc5/0x140 [jbd2]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0375e52>] jbd2_complete_transaction+0x52/0xa0 [jbd2]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0732da2>] ldiskfs_sync_file+0x2e2/0x320 [ldiskfs]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffa52760b0>] vfs_fsync_range+0x20/0x30</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0c8b651>] osd_object_sync+0xb1/0x160 [osd_ldiskfs]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0ab48a7>] tgt_sync+0xb7/0x270 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0dc3731>] ofd_sync_hdl+0x111/0x530 [ofd]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0aba1da>] tgt_request_handle+0xaea/0x1580 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0a5f80b>] ptlrpc_server_handle_request+0x24b/0xab0 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0a6313c>] ptlrpc_main+0xafc/0x1fc0 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffa50c1c71>] kthread+0xd1/0xe0</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffa5775c37>] ret_from_fork_nospec_end+0x0/0x39</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffffffffff>] 0xffffffffffffffff</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: LustreError: dumping log to /tmp/lustre-log.1572261743.2403</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: Pid: 2292, comm: ll_ost03_043 3.10.0-957.10.1.el7_lustre.x86_64 #1 SMP Sun May 26 21:48:35 UTC 2019</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: Call Trace:</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc03747c5>] jbd2_log_wait_commit+0xc5/0x140 [jbd2]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0375e52>] jbd2_complete_transaction+0x52/0xa0 [jbd2]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0732da2>] ldiskfs_sync_file+0x2e2/0x320 [ldiskfs]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffa52760b0>] vfs_fsync_range+0x20/0x30</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0c8b651>] osd_object_sync+0xb1/0x160 [osd_ldiskfs]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0ab48a7>] tgt_sync+0xb7/0x270 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0dc3731>] ofd_sync_hdl+0x111/0x530 [ofd]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0aba1da>] tgt_request_handle+0xaea/0x1580 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0a5f80b>] ptlrpc_server_handle_request+0x24b/0xab0 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: LNet: Service thread pid 2403 completed after 200.29s. This indicates the system was overloaded (too many service threads, or there were not enough hardware
resources).</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: LNet: Skipped 48 previous similar messages</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffc0a6313c>] ptlrpc_main+0xafc/0x1fc0 [ptlrpc]</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffa50c1c71>] kthread+0xd1/0xe0</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffa5775c37>] ret_from_fork_nospec_end+0x0/0x39</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black">Oct 28 11:22:23 pazlustreoss001 kernel: [<ffffffffffffffff>] 0xffffffffffffffff</span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
</div>
<p class="MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
</div>
</div>
<br>
</div>
</div>
</body>
</html>