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-2027 Lustre <p>When enabled (by default) /proc/fs/lustre/obdfilter/*/writethrough_cache_enable reports an erroneous number which appears to continue to increment upward. </p> <p>Speaking with Oleg about this, he believes it to be a bug. Per the manual this should either be 1 or 0 indicating enable or disable</p> LU-2027

writethrough_cache_enable reports erroneous number

Bug Minor Resolved Cannot Reproduce Jian Yu Colin Faber [X] Tue, 25 Sep 2012 14:22:47 +0000 Mon, 26 Mar 2018 05:22:40 +0000 Mon, 26 Mar 2018 05:22:39 +0000 Lustre 2.2.0 0 3 <p>Yujian</p> <p>Could you please look into this one?</p> <p>Thanks</p> <p>Peter</p> <p>Hello Colin,</p> <p>I provisioned a test cluster (2 clients, 1 combined MGS/MDS and 1 OSS with 7 OSTs) with Lustre b2_2 build <a href="http://build.whamcloud.com/job/lustre-b2_2/17/" class="external-link" target="_blank" rel="nofollow noopener">http://build.whamcloud.com/job/lustre-b2_2/17/</a> and set up a fresh Lustre filesystem by running llmount.sh. After the filesystem was up, I ran the following commands on the OSS node:</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>[root@fat-intel-4 ~]# df Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 20642428 1985276 17608576 11% / tmpfs 12298420 0 12298420 0% /dev/shm /dev/sdc5 2064208 107448 1851904 6% /mnt/ost1 /dev/sdc6 2064208 107448 1851904 6% /mnt/ost2 /dev/sdc7 2064208 107448 1851904 6% /mnt/ost3 /dev/sdc8 2064208 107448 1851904 6% /mnt/ost4 /dev/sdc9 2064208 107448 1851904 6% /mnt/ost5 /dev/sdc10 2064208 107448 1851904 6% /mnt/ost6 /dev/sdc11 2064208 107448 1851904 6% /mnt/ost7 [root@fat-intel-4 ~]# lctl get_param obdfilter.*.writethrough_cache_enable obdfilter.lustre-OST0000.writethrough_cache_enable=1 obdfilter.lustre-OST0001.writethrough_cache_enable=1 obdfilter.lustre-OST0002.writethrough_cache_enable=1 obdfilter.lustre-OST0003.writethrough_cache_enable=1 obdfilter.lustre-OST0004.writethrough_cache_enable=1 obdfilter.lustre-OST0005.writethrough_cache_enable=1 obdfilter.lustre-OST0006.writethrough_cache_enable=1 [root@fat-intel-4 ~]# lctl set_param obdfilter.*.writethrough_cache_enable 0 obdfilter.lustre-OST0000.writethrough_cache_enable=0 obdfilter.lustre-OST0001.writethrough_cache_enable=0 obdfilter.lustre-OST0002.writethrough_cache_enable=0 obdfilter.lustre-OST0003.writethrough_cache_enable=0 obdfilter.lustre-OST0004.writethrough_cache_enable=0 obdfilter.lustre-OST0005.writethrough_cache_enable=0 obdfilter.lustre-OST0006.writethrough_cache_enable=0 [root@fat-intel-4 ~]# lctl get_param obdfilter.*.writethrough_cache_enable obdfilter.lustre-OST0000.writethrough_cache_enable=0 obdfilter.lustre-OST0001.writethrough_cache_enable=0 obdfilter.lustre-OST0002.writethrough_cache_enable=0 obdfilter.lustre-OST0003.writethrough_cache_enable=0 obdfilter.lustre-OST0004.writethrough_cache_enable=0 obdfilter.lustre-OST0005.writethrough_cache_enable=0 obdfilter.lustre-OST0006.writethrough_cache_enable=0 [root@fat-intel-4 ~]# lctl set_param obdfilter.*.writethrough_cache_enable 1 obdfilter.lustre-OST0000.writethrough_cache_enable=1 obdfilter.lustre-OST0001.writethrough_cache_enable=1 obdfilter.lustre-OST0002.writethrough_cache_enable=1 obdfilter.lustre-OST0003.writethrough_cache_enable=1 obdfilter.lustre-OST0004.writethrough_cache_enable=1 obdfilter.lustre-OST0005.writethrough_cache_enable=1 obdfilter.lustre-OST0006.writethrough_cache_enable=1 [root@fat-intel-4 ~]# lctl get_param obdfilter.*.writethrough_cache_enable obdfilter.lustre-OST0000.writethrough_cache_enable=1 obdfilter.lustre-OST0001.writethrough_cache_enable=1 obdfilter.lustre-OST0002.writethrough_cache_enable=1 obdfilter.lustre-OST0003.writethrough_cache_enable=1 obdfilter.lustre-OST0004.writethrough_cache_enable=1 obdfilter.lustre-OST0005.writethrough_cache_enable=1 obdfilter.lustre-OST0006.writethrough_cache_enable=1 </pre> </div></div> <p>As we can see, the value of writethrough_cache_enable was correct.</p> <p>I also did the same test on the following Lustre builds:<br/> Lustre Build: <a href="http://build.whamcloud.com/job/lustre-master/898/" class="external-link" target="_blank" rel="nofollow noopener">http://build.whamcloud.com/job/lustre-master/898/</a><br/> Lustre Build: <a href="http://build.whamcloud.com/job/lustre-b2_3/24/" class="external-link" target="_blank" rel="nofollow noopener">http://build.whamcloud.com/job/lustre-b2_3/24/</a><br/> Lustre Build: <a href="http://build.whamcloud.com/job/lustre-b2_2/21/" class="external-link" target="_blank" rel="nofollow noopener">http://build.whamcloud.com/job/lustre-b2_2/21/</a></p> <p>All worked properly.</p> <p>Could you please tell me what tests/operations you performed to hit the erroneous number issue? Thanks.</p> <p>Colin</p> <p>Could you also please clarify whether this is a vanilla 2.2 release or whether there have been any modifications made to it?</p> <p>Thanks</p> <p>Peter</p> <p>Close old ticket. If the issue occurs again, please feel free to reopen the ticket.</p> Development Rank 1|hzv3v3: Rank (Obsolete) 4154 Severity