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-4109 Lustre <p>While testing HSM features, acceptance-small was run with test results at: <a href="https://maloo.whamcloud.com/test_sessions/4574cfe8-35e1-11e3-b051-52540035b04c" class="external-link" target="_blank" rel="nofollow noopener">https://maloo.whamcloud.com/test_sessions/4574cfe8-35e1-11e3-b051-52540035b04c</a></p> <p>From the test_log:</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>== sanity test 57b: default LOV EAs are stored inside large inodes ===== 13:06:10 (1381781170) mcreating 100 files total: 100 creates in 0.17 seconds: 572.16 creates/second Filesystem 1K-blocks Used Available Use% Mounted on mds@o2ib:/scratch 25088052 942228 22886476 4% /lustre/scratch opening files to create objects/EAs Filesystem 1K-blocks Used Available Use% Mounted on mds@o2ib:/scratch 25088052 942228 22886720 4% /lustre/scratch sanity test_57b: @@@@@@ FAIL: MDC before 15214812 != after 15214800 Trace dump: = /usr/lib64/lustre/tests/test-framework.sh:4264:error_noexit() = /usr/lib64/lustre/tests/test-framework.sh:4291:error() = /usr/lib64/lustre/tests/sanity.sh:4670:test_57b() = /usr/lib64/lustre/tests/test-framework.sh:4530:run_one() = /usr/lib64/lustre/tests/test-framework.sh:4563:run_one_logged() = /usr/lib64/lustre/tests/test-framework.sh:4433:run_test() = /usr/lib64/lustre/tests/sanity.sh:4678:main() </pre> </div></div> Lustre 2.5.0-RC1, el6<br/> <br/> OpenSFS cluster with combined MGS/MDS (c03), single OSS (c04) with two OSTs, archive MGS/MDS (c05), archive OST (c06) with two OSTs, archive OST2 (c07) with two OSTs, eight clients; one agent + client(c08), one robinhood/db + client(c09) and others just running as Lustre clients (c09, c10, c11, c12, c13,c14, c15) LU-4109

sanity test_57b failure: 'MDC before 15214812 != after 15214800'

Bug Minor Resolved Fixed Bruno Faccini James Nunez HSM Wed, 16 Oct 2013 03:18:21 +0000 Tue, 14 Dec 2021 01:11:35 +0000 Wed, 27 Nov 2013 08:30:30 +0000 Lustre 2.5.0 Lustre 2.6.0 Lustre 2.5.2 0 4 <p>Bruno</p> <p>Could you please help with this one?</p> <p>Thanks</p> <p>Peter</p> <p>Should be trivial to increase the margin from 8 to 16 or something. Since we create 100 files in the test, we should still be pretty safe.</p> <p>Andreas, I would like to better understand what sanity/test_57b() tries to detect.<br/> So, what could cause this ? Wide default striping vs Inode size at mke2fs ? <br/> If yes, we could anticipate it and use/compute an appropriated margin, no ? If no, what did I miss and misunderstand?</p> <p>James, do you remember these parameters value during your failing test ?</p> <p>Bruno, <br/> The file system was set up and run with pretty much all default settings. I think the striping for this set of tests was a single stripe with a single OSS with two OSTs. So, default striping, but not wide. </p> <p>James</p> <p>Bruno, test_57b is trying to detect if the LOV EA is too large to fit into the MDT inode for some reason (e.g. formatted with too-small inodes, default LOV EA becomes too large, etc). If 100 files are created and 100 blocks are allocated then the test fails. In this case, only a few blocks are allocated (e.g. llog files, ChangeLog, etc), and the test shouldn't fail, so increasing the margin a small amount is fine.</p> <p>Ok it was also my understanding that if LOV EA can not fit into MDT inode this will need at least 1 additional block per file, so in this case why not do the reverse test and simply detect if the number of free blocks decreased of 100+ blocks ?</p> <p>What if the xattrs are stored more efficiently than 1 per 4kB (e.g. MDT formatted with 1kB blocksize)? I don't mind having a larger margin, but I think the test could start to fail silently if the error margin is too large. I think 32-64kB is large enough to avoid future problems, and smaller than the 400kB that would be seen with 100 4kB blocks or even 400 1kB blocks. </p> <p>Patch raising threshold, to detect out-of inode LOV EA alloc, from 8 to 16 is at <a href="http://review.whamcloud.com/8156" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/8156</a>.</p> <p>Patch has landed.</p> <p>I'm seeing a similar (same?) error again in 2.5.1-RC3 with error "sanity test_57b: @@@@@@ FAIL: MDC before 46667332 != after 46667320". The results are at <a href="https://maloo.whamcloud.com/test_sessions/f6c5b8e6-aac8-11e3-a41c-52540035b04c" class="external-link" target="_blank" rel="nofollow noopener">https://maloo.whamcloud.com/test_sessions/f6c5b8e6-aac8-11e3-a41c-52540035b04c</a></p> <p>I'm running on the OpenSFS cluster with similar set up to what was originally reported. </p> <p>It looks like this patch was not back ported to b2_5. </p> <p>Patch for b2_5 at <a href="http://review.whamcloud.com/#/c/9652/" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/#/c/9652/</a></p> <p><a href="http://review.whamcloud.com/#/c/9652/" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/#/c/9652/</a> landed to b2_5.</p> Related LU-9661 Development Rank 1|hzw5tb: Rank (Obsolete) 11065 Severity