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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"> I have a situation where an apache web server is trying to locate the IndexDocument for a directory on a gluster volume. This URL is being hit roughly 20 times per second. There is only 1 file in this directory. However,
the parent directory does have a large number of items (+123,000 files and dirs) and we are performing operations to move these files into 2 levels of subdirs.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We are seeing very slow response times (around 8 seconds) in apache and also when trying to ls on this dir. Before we started the migrations to move files on the large parent dir into 2 sub levels, we weren’t aware of a problem.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@web-02 images]# time ls -l dir1/get/ | wc -l<o:p></o:p></p>
<p class="MsoNormal">2<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">real 0m8.114s<o:p></o:p></p>
<p class="MsoNormal">user 0m0.002s<o:p></o:p></p>
<p class="MsoNormal">sys 0m0.014s<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Other directories with only 1 item return very quickly (<1 sec).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@Web-01 images]# time ls -l dir1/tmp1/ | wc -l<o:p></o:p></p>
<p class="MsoNormal">2<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">real 0m0.014s<o:p></o:p></p>
<p class="MsoNormal">user 0m0.003s<o:p></o:p></p>
<p class="MsoNormal">sys 0m0.006s<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m just trying to understand what would slow down this operation so much. Is it the high frequency of attempts to read the directory (apache hits to dir1/get/) ? Do the move operations on items in the parent directory have any impact?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Some background info:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@web-02 images]# gluster --version<o:p></o:p></p>
<p class="MsoNormal">glusterfs 3.7.20 built on Jan 30 2017 15:39:29<o:p></o:p></p>
<p class="MsoNormal">Repository revision: git://git.gluster.com/glusterfs.git<o:p></o:p></p>
<p class="MsoNormal">Copyright (c) 2006-2011 Gluster Inc. <http://www.gluster.com><o:p></o:p></p>
<p class="MsoNormal">GlusterFS comes with ABSOLUTELY NO WARRANTY.<o:p></o:p></p>
<p class="MsoNormal">You may redistribute copies of GlusterFS under the terms of the GNU General Public License.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@web-02 images]# gluster vol info<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Volume Name: web_vol1<o:p></o:p></p>
<p class="MsoNormal">Type: Replicate<o:p></o:p></p>
<p class="MsoNormal">Volume ID: 0d63de20-c9c2-4931-b4a3-6aed5ae28057<o:p></o:p></p>
<p class="MsoNormal">Status: Started<o:p></o:p></p>
<p class="MsoNormal">Number of Bricks: 1 x 2 = 2<o:p></o:p></p>
<p class="MsoNormal">Transport-type: tcp<o:p></o:p></p>
<p class="MsoNormal">Bricks:<o:p></o:p></p>
<p class="MsoNormal">Brick1: web-01:/export/brick1/web_vol1_brick1<o:p></o:p></p>
<p class="MsoNormal">Brick2: web-02:/export/brick1/web_vol1_brick1<o:p></o:p></p>
<p class="MsoNormal">Options Reconfigured:<o:p></o:p></p>
<p class="MsoNormal">performance.readdir-ahead: on<o:p></o:p></p>
<p class="MsoNormal">performance.io-thread-count: 32<o:p></o:p></p>
<p class="MsoNormal">performance.cache-size: 512MB<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any insight would be gratefully received.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal"> Aaron<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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