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</o:shapelayout></xml><![endif]--></head><body lang=DE-AT link=blue vlink=purple><div class=WordSection1><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Hi all,<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-US style='color:#1F497D;mso-fareast-language:DE-AT'>I just tested the latest OpenVZ kernel 2.6.32 (bykovsky) from today with sysbench, I just got 63.12 Requests/sec executed (see below).<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>2.6.18 and 2.6.24 OpenVZ Kernels performs well, I got 1074.81 Requests/sec executed. </span><span lang=EN-US style='color:#1F497D;mso-fareast-language:DE-AT'>What's wrong here, why is the 2.6.32 branch so slow regarding fsyns/sec? (I am using ext3)<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>____<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>OpenVZ 2.6.24:~# sysbench --test=fileio --file-num=1 --file-total-size=50G --file-fsync-all=on --file-test-mode=seqrewr --max-time=100 --file-block-size=4096 --max-requests=0 run<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>sysbench 0.4.12: multi-threaded system evaluation benchmark<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Running the test with following options:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Number of threads: 1<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Extra file open flags: 0<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>1 files, 50Gb each<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>50Gb total file size<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Block size 4Kb<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Calling fsync() after each write operation.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Using synchronous I/O mode<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Doing sequential rewrite test<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Threads started!<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Time limit exceeded, exiting...<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Done.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Operations performed: 0 Read, 107485 Write, 107485 Other = 214970 Total<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Read 0b Written 419.86Mb Total transferred 419.86Mb (4.1985Mb/sec)<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> 1074.81 Requests/sec executed<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Test execution summary:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> total time: 100.0033s<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> total number of events: 107485<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> total time taken by event execution: 99.9460<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> per-request statistics:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> min: 0.54ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> avg: 0.93ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> max: 97.34ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> approx. 95 percentile: 0.87ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Threads fairness:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> events (avg/stddev): 107485.0000/0.00<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> execution time (avg/stddev): 99.9460/0.00<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>_____<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Testing newest Kernel: 2.6.32-bykovsky.1 #1 SMP Mon Aug 23 19:59:54 MSD 2010 x86_64<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>I just got 63.12 Requests/sec executed. Here are the details, can someone reproduce this?<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>_____<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>OpenVZ 2.6.32:~# sysbench --test=fileio --file-num=1 --file-total-size=50G --file-fsync-all=on --file-test-mode=seqrewr --max-time=100 --file-block-size=4096 --max-requests=0 run<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>sysbench 0.4.12: multi-threaded system evaluation benchmark<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Running the test with following options:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Number of threads: 1<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Extra file open flags: 0<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>1 files, 50Gb each<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>50Gb total file size<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Block size 4Kb<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Calling fsync() after each write operation.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Using synchronous I/O mode<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Doing sequential rewrite test<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Threads started!<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Time limit exceeded, exiting...<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Done.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Operations performed: 0 Read, 6312 Write, 6312 Other = 12624 Total<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Read 0b Written 24.656Mb Total transferred 24.656Mb (252.46Kb/sec)<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> 63.12 Requests/sec executed<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Test execution summary:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> total time: 100.0070s<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> total number of events: 6312<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> total time taken by event execution: 99.9838<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> per-request statistics:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> min: 7.70ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> avg: 15.84ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> max: 260.40ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> approx. 95 percentile: 16.70ms<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>Threads fairness:<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> events (avg/stddev): 6312.0000/0.00<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'> execution time (avg/stddev): 99.9838/0.00<o:p></o:p></span></p><p class=MsoPlainText><span style='color:#1F497D;mso-fareast-language:DE-AT'>___<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Br, Martin<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> users-bounces@openvz.org [mailto:users-bounces@openvz.org] <b>On Behalf Of </b>Dietmar Maurer<br><b>Sent:</b> Dienstag, 24. August 2010 10:36<br><b>To:</b> users@openvz.org<br><b>Subject:</b> [Users] slow fsync rate<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>Hi all,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>we observe very slow fsync rates on newer 2.6.32 kernel with OpenVZ:<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>It is possible to reproduce the problem with sysbench:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US># sysbench --test=fileio --file-num=1 --file-total-size=50G --file-fsync-all=on --file-test-mode=seqrewr --max-time=100 --file-block-size=4096 --max-requests=0 run<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Requests/sec executed is considerable slower on OpenVZ kernel (factor 20 on Intel Modular Server).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Can someone reproduce that problem?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>- Dietmar<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></body></html>