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<p class="MsoNormal">All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am having some difficulties with my lustre system. It seems to be when someone is doing quite a bit of reads/writes.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My layout:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">A large Volume Group off a DDN connected via infiniband.<o:p></o:p></p>
<p class="MsoNormal">This is broken into several Logical Volumes. Some are just regular ext3/4 filesystems. Quite a few are partitioned out (in 4TB chunks) for OSTs.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have 3 lustre filesystems: home, scratch and work.<o:p></o:p></p>
<p class="MsoNormal">Home consists of a single OST<o:p></o:p></p>
<p class="MsoNormal">Scratch consists of 2 OSTs<o:p></o:p></p>
<p class="MsoNormal">Work consists of 10 OSTs<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Each filesystem has its own combined MGS/MGT<o:p></o:p></p>
<p class="MsoNormal">Each OSS has 2 OSTs where possible<o:p></o:p></p>
<p class="MsoNormal">Each MGS will also serve one OST<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have 8 systems that are OSSes (The MGSes are also among those 8)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Now, ONE of my nodes (an OSSes that is only serving 2 OSTs) has a helluva load:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@nas-0-3 ~]# uptime<o:p></o:p></p>
<p class="MsoNormal">15:34:06 up 77 days, 22:39, 1 user, load average: 352.59, 339.80, 318.11<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I see lots of:<o:p></o:p></p>
<p class="MsoNormal">Lustre: work-OST0004: slow commitrw commit 91s due to heavy IO load<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">And:<o:p></o:p></p>
<p class="MsoNormal">Dec 13 15:32:48 nas-0-3 kernel: LustreError: 6413:0:(ldlm_lib.c:1919:target_send_reply_msg()) @@@ processing error (-107) req@ffff8105c557ac00 x1381121762230130/t0 o400-><?>@<?>:0/0 lens 192/0 e 0 to 0 dl 1323819184 ref 1 fl Interpret:H/0/0
rc -107/0<o:p></o:p></p>
<p class="MsoNormal">Dec 13 15:32:48 nas-0-3 kernel: LustreError: 6413:0:(ldlm_lib.c:1919:target_send_reply_msg()) Skipped 1900 previous similar messages<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Not sure what that one means, but it seems significant.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Things get VERY slow and start timing out. Users see it as the system ‘hanging’.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Could someone point me in the right direction for figuring out the culprit here?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="color:#1F497D">Brian Andrus<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">ITACS/Research Computing<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Naval Postgraduate School<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Monterey, California<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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