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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Hello Malhal,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Thank you. Actually I don’t see the parameter Cache_FDs in our ganesha config. But when I trace LRU processing I see that almost no FDs get released. And the number of FDs given in the log messages
doesn’t match what I see in /proc/<pid of ganesha>/fd/. I see 512k open files while the logfile give 600k. Even 4hours since the I suspended the node and all i/o activity stopped I see 500k open files and LRU processing doesn’t close any of them.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">This looks like a bug in gpfs.nfs-ganesha-2.5.3-ibm036.10.el7. I’ll open a case with IBM. We did see gansha to fail to open new files and hence client requests to fail. I assume that 500K FDs compared
to 10K FDs as before create some notable overhead for ganesha, spectrum scale and kernel and withdraw resources from samba.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I’ll post to the list once we got some results.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Cheers,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Heiner<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Start of LRU processing<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1027<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :F_DBG :formeropen=607025 totalwork=0 workpass=51350 totalclosed:6<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1027<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Actually processed 50 entries on lane 1027 closing 0 descriptors<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1028<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :F_DBG :formeropen=607025 totalwork=0 workpass=51400 totalclosed:6<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1028<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Actually processed 50 entries on lane 1028 closing 0 descriptors<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">End of log<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1029<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Actually processed 50 entries on lane 1029 closing 0 descriptors<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1030<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :F_DBG :formeropen=607025 totalwork=0 workpass=51500 totalclosed:6<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Reaping up to 50 entries from lane 1030<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run_lane :INODE LRU :DEBUG :Actually processed 50 entries on lane 1030 closing 0 descriptors<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :DEBUG :After work, open_fd_count:607024 count:29503718 fdrate:1908874353 threadwait=9<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">2019-09-23 11:37:30 : epoch 00100524 : nas12ces01 : gpfs.ganesha.nfsd-100816[cache_lru] lru_run :INODE LRU :F_DBG :currentopen=607024 futility=0 totalwork=51550 biggest_window=335544 extremis=0 lanes=1031
fds_lowat=167772<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black"><gpfsug-discuss-bounces@spectrumscale.org> on behalf of Malahal R Naineni <mnaineni@in.ibm.com><br>
<b>Reply to: </b>gpfsug main discussion list <gpfsug-discuss@spectrumscale.org><br>
<b>Date: </b>Thursday, 19 September 2019 at 20:39<br>
<b>To: </b>"gpfsug-discuss@spectrumscale.org" <gpfsug-discuss@spectrumscale.org><br>
<b>Cc: </b>"gpfsug-discuss@spectrumscale.org" <gpfsug-discuss@spectrumscale.org><br>
<b>Subject: </b>Re: [gpfsug-discuss] Ganesha daemon has 400'000 open files - is this unusual?<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">NFSv3 doesn't have open/close requests, so nfs-ganesha opens a file for read/write when there is an NFSv3 read/write request. It does cache file descriptors, so its open count
can be very large. If you have 'Cache_FDs = true" in your config, ganesha aggressively caches file descriptors. <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Taking traces with COMPONENT_CACHE_INODE_LRU level set to full debug should give us better insight on what is happening when the the open file descriptors count is very high.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">When the I/O failure happens or when the open fd count is high, you could do the following:<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">1. ganesha_mgr set_log COMPONENT_CACHE_INODE_LRU FULL_DEBUG<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">2. wait for 90 seconds, then run<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">3. ganesha_mgr set_log COMPONENT_CACHE_INODE_LRU EVENT<br>
<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Regards, Malahal.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">----- Original message -----<br>
From: "Billich Heinrich Rainer (ID SD)" <heinrich.billich@id.ethz.ch><br>
Sent by: gpfsug-discuss-bounces@spectrumscale.org<br>
To: gpfsug main discussion list <gpfsug-discuss@spectrumscale.org><br>
Cc:<br>
Subject: [EXTERNAL] [gpfsug-discuss] Ganesha daemon has 400'000 open files - is this unusual?<br>
Date: Thu, Sep 19, 2019 7:51 PM<br>
<br>
<br>
<o:p></o:p></span></p>
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<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">Hello,</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">Is it usual to see 200’000-400’000 open files for a single ganesha process? Or does this indicate that something ist wrong?</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">We have some issues with ganesha (on spectrum scale protocol nodes) reporting NFS3ERR_IO in the log. I noticed that the affected nodes have a large number of open files,
200’000-400’000 open files per daemon (and 500 threads and about 250 client connections). Other nodes have 1’000 – 10’000 open files by ganesha only and don’t show the issue.</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">If someone could explain how ganesha decides which files to keep open and which to close that would help, too. As NFSv3 is stateless the client doesn’t open/close a file,
it’s the server to decide when to close it? We do have a few NFSv4 clients, too.</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">Are there certain access patterns that can trigger such a large number of open file? Maybe traversing and reading a large number of small files?
</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">Thank you,</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">Heiner</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">I did count the open files by counting the entries in /proc/<pid of ganesha>/fd/ . With several 100k entries I failed to do a ‘ls -ls’ to list all the symbolic links,
hence I can’t relate the open files to different exports easily.</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">I did post this to the ganesha mailing list, too.</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif">-- </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span lang="DE" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">=======================</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span lang="DE" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">Heinrich Billich</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span lang="DE" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">ETH Zürich</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">Informatikdienste</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">Tel.: +41 44 632 72 56</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">heinrich.billich@id.ethz.ch</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#18376A">========================</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-family:"Arial",sans-serif"> </span><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p></o:p></span></p>
<p style="margin:0cm;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
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