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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt'>This is how I installed lustre clients (only showing packages installed steps). <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>cat > /etc/yum.repos.d/lustre.repo << EOF<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>[hpddLustreserver]<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>name=CentOS- - Lustre<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>baseurl=https://downloads.whamcloud.com/public/lustre/latest-release/el7/server/<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>gpgcheck=</span><span style='font-size:9.0pt;font-family:Menlo;color:#272AD8'>0</span><span style='font-size:9.0pt;font-family:Menlo;color:black'><o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Helvetica'><o:p> </o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>[e2fsprogs]<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>name=CentOS- - Ldiskfs<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>baseurl=https://downloads.whamcloud.com/public/e2fsprogs/latest/el7/<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>gpgcheck=</span><span style='font-size:9.0pt;font-family:Menlo;color:#272AD8'>0</span><span style='font-size:9.0pt;font-family:Menlo;color:black'><o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Helvetica'><o:p> </o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>[hpddLustreclient]<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>name=CentOS- - Lustre<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>baseurl=https://downloads.whamcloud.com/public/lustre/latest-release/el7/client/<o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>gpgcheck=</span><span style='font-size:9.0pt;font-family:Menlo;color:#272AD8'>0</span><span style='font-size:9.0pt;font-family:Menlo;color:black'><o:p></o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>EOF<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>yum install lustre-client -y<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>reboot<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='color:black'>From: </span></b><span style='color:black'>"Moreno Diego (ID SIS)" <diego.moreno@id.ethz.ch><br><b>Date: </b>Friday, December 13, 2019 at 2:55 AM<br><b>To: </b>Pinkesh Valdria <pinkesh.valdria@oracle.com>, "lustre-discuss@lists.lustre.org" <lustre-discuss@lists.lustre.org><br><b>Subject: </b>Re: [lustre-discuss] Degraded read performance with Large Bulk IO (16MB RPC)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p></div><p class=MsoNormal><span style='font-size:11.0pt'>From what I can see they exist on my 2.12.3 client node:</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'>[root@rufus4 ~]# lctl list_param -R llite | grep max_read_ahead</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'>llite.reprofs-ffff9f7c3b4a8800.max_read_ahead_mb</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'>llite.reprofs-ffff9f7c3b4a8800.max_read_ahead_per_file_mb</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'>llite.reprofs-ffff9f7c3b4a8800.max_read_ahead_whole_mb</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'>Regards,</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'> </span><o:p></o:p></p><div><p class=MsoNormal><span style='font-size:11.0pt;color:black'>Diego</span><o:p></o:p></p></div><p class=MsoNormal><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt'> </span><o:p></o:p></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:.5in'><b><span style='color:black'>From: </span></b><span style='color:black'>Pinkesh Valdria <pinkesh.valdria@oracle.com><br><b>Date: </b>Wednesday, 11 December 2019 at 17:46<br><b>To: </b>"Moreno Diego (ID SIS)" <diego.moreno@id.ethz.ch>, "lustre-discuss@lists.lustre.org" <lustre-discuss@lists.lustre.org><br><b>Subject: </b>Re: [lustre-discuss] Degraded read performance with Large Bulk IO (16MB RPC)</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>I was not able to find those parameters on my client nodes, OSS or MGS nodes. Here is how I was extracting all parameters . </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in;background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>mkdir -p lctl_list_param_R/</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in;background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>cd lctl_list_param_R/</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in;background:white'><span style='font-size:9.0pt;font-family:Menlo;color:black'>lctl list_param -R * > lctl_list_param_R</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>[opc@lustre-client-1 lctl_list_param_R]$ less lctl_list_param_R | grep ahead</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsbv-ffff98231c3bc000.statahead_agl</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsbv-ffff98231c3bc000.statahead_max</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsbv-ffff98231c3bc000.statahead_running_max</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsnvme-ffff98232c30e000.statahead_agl</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsnvme-ffff98232c30e000.statahead_max</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsnvme-ffff98232c30e000.statahead_running_max</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>[opc@lustre-client-1 lctl_list_param_R]$</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>I also tried these commands: </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt'> </span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt'>Not working: </span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt'>On client nodes</span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>lctl get_param llite.lfsbv-*.max_read_ahead_mb</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>error: get_param: param_path 'llite/lfsbv-*/max_read_ahead_mb': No such file or directory</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>[opc@lustre-client-1 lctl_list_param_R]$</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt'> </span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt'>Works </span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt'>On client nodes</span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>lctl get_param llite.*.statahead_agl</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsbv-ffff98231c3bc000.statahead_agl=1</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>llite.lfsnvme-ffff98232c30e000.statahead_agl=1</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>[opc@lustre-client-1 lctl_list_param_R]$</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:.5in'><b><span style='color:black'>From: </span></b><span style='color:black'>"Moreno Diego (ID SIS)" <diego.moreno@id.ethz.ch><br><b>Date: </b>Tuesday, December 10, 2019 at 2:06 AM<br><b>To: </b>Pinkesh Valdria <pinkesh.valdria@oracle.com>, "lustre-discuss@lists.lustre.org" <lustre-discuss@lists.lustre.org><br><b>Subject: </b>Re: [lustre-discuss] Degraded read performance with Large Bulk IO (16MB RPC)</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>With that kind of degradation performance on read I would immediately think on llite’s max_read_ahead parameters on the client. Specifically these 2:</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>max_read_ahead_mb: total amount of MB allocated for read ahead, usually quite low for bandwidth benchmarking purposes and when there’re several files per client</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>max_read_ahead_per_file_mb: the default is quite low for 16MB RPCs (only a few RPCs per file)</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>You probably need to check the effect increasing both of them.</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'>Regards,</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><div><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt;color:black'>Diego</span><o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='margin-left:1.0in'><b><span style='color:black'>From: </span></b><span style='color:black'>lustre-discuss <lustre-discuss-bounces@lists.lustre.org> on behalf of Pinkesh Valdria <pinkesh.valdria@oracle.com><br><b>Date: </b>Tuesday, 10 December 2019 at 09:40<br><b>To: </b>"lustre-discuss@lists.lustre.org" <lustre-discuss@lists.lustre.org><br><b>Subject: </b>[lustre-discuss] Degraded read performance with Large Bulk IO (16MB RPC)</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p></div><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'>I was expecting better or same read performance with Large Bulk IO (16MB RPC), but I see degradation in performance. Do I need to tune any other parameter to benefit from Large Bulk IO? Appreciate if I can get any pointers to troubleshoot further. </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><b><span style='font-size:11.0pt'>Throughput before </span></b><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>Read: 2563 MB/s</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l2 level1 lfo2'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>Write: 2585 MB/s</span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><b><span style='font-size:11.0pt'>Throughput after</span></b><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l1 level1 lfo4'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>Read: 1527 MB/s. (down by ~1025)</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l1 level1 lfo4'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>Write: 2859 MB/s</span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><b><span style='font-size:11.0pt'>Changes I did are: </span></b><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'>On oss</span><o:p></o:p></p><p class=p1 style='margin-left:1.5in;text-indent:-.25in;mso-list:l1 level1 lfo4'><![if !supportLists]><span style='font-family:"Calibri",sans-serif'><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><i>lctl set_param obdfilter.lfsbv-*.brw_size=16</i><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'>On clients </span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l3 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>unmounted and remounted</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l3 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:10.0pt'>lctl set_param <i>osc.lfsbv-OST*.max_pages_per_rpc</i>=4096 (got auto-updated after re-mount)</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l3 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>lctl set_param osc.*.max_rpcs_in_flight=64 (Had to manually increase this to 64, since after re-mount, it was auto-set to 8, but read/write performance was poor)</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l3 level1 lfo6'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:11.0pt'>lctl set_param osc.*.max_dirty_mb=2040. (setting the value to 2048 was failing with : Numerical result out of range error. Previously it was set to 2000 when I got good performance. </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt;color:black'>My other settings: </span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l0 level1 lfo8;background:white'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:9.0pt;font-family:Menlo;color:black'>lnetctl net add --net tcp1 --if $interface –peer-timeout 180 –peer-credits 128 –credits 1024</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l0 level1 lfo8;background:white'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:9.0pt;font-family:Menlo;color:black'>echo "options ksocklnd nscheds=10 sock_timeout=100 credits=2560 peer_credits=63 enable_irq_affinity=0" > /etc/modprobe.d/ksocklnd.conf</span><o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.5in;text-indent:-.25in;mso-list:l0 level1 lfo8;background:white'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span style='font-size:9.0pt;font-family:Menlo;color:black'>lfs setstripe -c 1 -S 1M /mnt/mdt_bv/test1</span><o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'><span style='font-size:11.0pt'> </span><o:p></o:p></p></div></body></html>