https://jira.whamcloud.com This file is an XML representation of an issue en-us 9.4.14 940014 05-12-2023 https://jira.whamcloud.com/browse/LU-4953 Lustre <p>If I double mount a client (for example with MOUNT_2=y llmount.sh) then the second mount point will have a missing /proc/fs/lustre/lmv/*/target_obds directory.</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>u:~# umount /mnt/lustre u:~# umount /mnt/lustre2 #### u:~# mount -o user_xattr,flock u@tcp:/lustre /mnt/lustre -t lustre u:~# ls /proc/fs/lustre/lmv/ lustre-clilmv-ffff8801f6d64e60 u:~# ls /proc/fs/lustre/lmv/lustre-clilmv-ffff8801f6d64e60/ activeobd desc_uuid md_stats numobd placement target_obd target_obds uuid u:~# ls -l /proc/fs/lustre/lmv/lustre-clilmv-ffff8801f6d64e60/target_obds/ total 0 lrwxrwxrwx 1 root root 48 Apr 24 12:49 lustre-MDT0000-mdc-ffff8801f6d64e60 -&gt; ../../../mdc/lustre-MDT0000-mdc-ffff8801f6d64e60 u:~# u:~# mount -o user_xattr,flock u@tcp:/lustre /mnt/lustre2 -t lustre u:~# ls /proc/fs/lustre/lmv/ lustre-clilmv-ffff8801f487f778 lustre-clilmv-ffff8801f6d64e60 u:~# ls /proc/fs/lustre/lmv/lustre-clilmv-ffff8801f487f778 activeobd desc_uuid md_stats numobd placement target_obd uuid u:~# </pre> </div></div> <p>I see this when I unmount the second client mount:</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>[ 263.149071] LustreError: 3790:0:(lmv_obd.c:761:lmv_disconnect()) /proc/fs/lustre/lmv/lustre-clilmv-ffff8802169bc688/target_obds missing </pre> </div></div> LU-4953

/proc/fs/lustre/lmv/*/target_obds missing on second mounts

Bug Critical Resolved Fixed Bob Glossman John Hammond lmv lprocfs mq313 patch Thu, 24 Apr 2014 17:55:32 +0000 Fri, 23 May 2014 19:08:06 +0000 Fri, 23 May 2014 19:08:06 +0000 Lustre 2.6.0 Lustre 2.6.0 0 3 <p>James, can you comment here?</p> <p>Yep I can duplicate this problem. Let me look into it.</p> <p>Okay I figured it out. The problem is the use of procsym itself. I created procsym so you have top level symlinks to point to another top level proc entry. Examples are lod -&gt; lov and osp -&gt; osc. A procsym exist once per object type whereas in this case the target_obds directories exist for each object instance.So we can't use the procsym field in obd_type. The reason it showed up in lmv and not lov is because I was not checking in lov if proc_sym was already set. This means lov is leaking memory on each module unload. This bug also exist in the upstream Lustre client.</p> <p>Please note this problem also exist in the 2.4 and 2.5 code base as well. In that case we have a single prod_dir_entry in each module even tho multiple instances need to be created. Thus we have memory leaks with module unloads as well.</p> <p>Patch at <a href="http://review.whamcloud.com/#/c/10192" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/#/c/10192</a>.</p> <p>I take it back about upstream. It does handle this correctly. We will need patches for b2_5 and possible b2_4 tho.</p> <p>Patch landed for master. Need to make patch for b2_5 and possible b2_4 as well.</p> <p>Patch landed to Master. Flagged for backport to b2_5. Closing ticket for fix in Master. Please reopen if additional work (other than back porting) is needed.</p> Development Rank 1|hzwky7: Rank (Obsolete) 13705 Severity