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-487 Lustre <p>brw_read in llite client procfs stats file claims to measure in units of pages. For example:</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java"># cat /proc/fs/lustre/llite/lustre-ffff88000449a800/stats snapshot_time 1308264214.464257 secs.usecs dirty_pages_hits 1419716 samples [regs] dirty_pages_misses 833472 samples [regs] read_bytes 322963 samples [bytes] 1 2684356 154236888794 write_bytes 225001 samples [bytes] 0 125912 3323679002 brw_read 15285 samples [pages] 4096 4096 62607360 </pre> </div></div> <p>However, in <tt>./lustre/llite/lloop.c</tt> the tallying of the LPROC_LL_BRW_WRITE/READ counter increments by the value of: </p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java">page_count &lt;&lt; PAGE_CACHE_SHIFT </pre> </div></div> <p>Using this value has the effect of not measure pages, but the total bytes of the pages. A simple fix maybe to remove the PAGE_CACHE_SHIFT. Or, rename '<span class="error">&#91;pages&#93;</span>' to '<span class="error">&#91;bytes&#93;</span>' in the output.</p> LU-487

procfs stats file incorrectly records brw_read and brw_write values

Bug Minor Resolved Fixed Richard Henwood Richard Henwood Tue, 5 Jul 2011 15:34:52 +0000 Fri, 12 Aug 2011 15:19:46 +0000 Fri, 12 Aug 2011 15:19:46 +0000 Lustre 2.1.0 Lustre 1.8.6 Lustre 2.1.0 0 3 <p>Since the "read_bytes" and "write_bytes" entries already exist, it makes sense to remove the "&lt;&lt; PAGE_CACHE_SHIFT" and actually count in pages. It is also inconsistent that there is a brw_read stat, but not a brw_write stat...</p> <p>Can I query: </p> <p>Since this tally call is in lloop.c, it is only used during loopback testing.</p> <p>If this is the case, the stats brw_ records are the number of partial page request that took place during testing.</p> <p>so: brw_ in it's current state of limited use.</p> <p>So, to call out explicitly:</p> <p>It seems to me brw_ records can lead to miss-interpretation in their current state.</p> <p>How about omitting them entirely?</p> <p>change available at:</p> <p><a href="http://review.whamcloud.com/#change,1056" class="external-link" target="_blank" rel="nofollow noopener">http://review.whamcloud.com/#change,1056</a></p> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=client,distro=el5,ib_stack=ofa/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,client,el5,ofa #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=client,distro=el5,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,client,el5,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=i686,build_type=client,distro=el6,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » i686,client,el6,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=i686,build_type=client,distro=el5,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » i686,client,el5,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=server,distro=el6,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,server,el6,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=client,distro=sles11,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,client,sles11,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=client,distro=el6,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,client,el6,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=server,distro=el5,ib_stack=ofa/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,server,el5,ofa #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=client,distro=ubuntu1004,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,client,ubuntu1004,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=x86_64,build_type=server,distro=el5,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » x86_64,server,el5,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=i686,build_type=server,distro=el5,ib_stack=ofa/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » i686,server,el5,ofa #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=i686,build_type=server,distro=el5,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » i686,server,el5,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=i686,build_type=server,distro=el6,ib_stack=inkernel/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » i686,server,el6,inkernel #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Integrated in <span class="image-wrap" style=""><img src="http://build.whamcloud.com/images/16x16/blue.png" style="border: 0px solid black" /></span> <a href="http://build.whamcloud.com/job/lustre-master/./arch=i686,build_type=client,distro=el5,ib_stack=ofa/244/" class="external-link" target="_blank" rel="nofollow noopener">lustre-master » i686,client,el5,ofa #244</a><br/> <a href="https://jira.whamcloud.com/browse/LU-487" title="procfs stats file incorrectly records brw_read and brw_write values" class="issue-link" data-issue-key="LU-487"><del>LU-487</del></a> brw_<span class="error">&#91;read|write&#93;</span> stats to correctly counts number of pages.</p> <p>Oleg Drokin : <a href="http://git.whamcloud.com/gitweb?p=fs/lustre-release.git;a=shortlog;h=refs/heads/master&amp;a=commit&amp;h=6aea71f39238f370c02a2f293a01555cc653bd01" class="external-link" target="_blank" rel="nofollow noopener">6aea71f39238f370c02a2f293a01555cc653bd01</a><br/> Files : </p> <ul> <li>lustre/llite/lloop.c</li> </ul> <p>Fix merged into Master.</p> Development Epic papercut Rank 1|hzv8lz: Rank (Obsolete) 4929 Severity