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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi <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 are using DRBD to mail server shared storage, recently I feel the server is very slow, so I use iostat tools to monitoring disk status, when mail queue more than 10, the “await” value of parameter is very high. As below:<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>avg-cpu: %user %nice %system %iowait %steal %idle<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> 0.12 0.00 0.12 0.00 0.00 99.75<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>avg-cpu: %user %nice %system %iowait %steal %idle<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> 0.42 0.00 0.25 7.49 0.00 91.84<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>Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda 0.00 6752.00 0.00 308.00 0.00 44467.00 144.37 142.56 433.49 3.25 100.10<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda1 0.00 6701.00 0.00 285.00 0.00 40424.00 141.84 134.80 427.90 3.51 100.10<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda3 0.00 0.00 0.00 3.00 0.00 3.00 1.00 0.16 53.00 53.00 15.90<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda4 0.00 51.00 0.00 20.00 0.00 4040.00 202.00 7.60 570.15 46.80 93.60<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>drbd0 0.00 0.00 0.00 57.00 0.00 456.00 8.00 160.15 5144.61 17.58 100.20<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><p class=MsoNormal><span lang=EN-US>Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda 0.00 548.51 0.00 234.65 0.00 5548.51 23.65 20.97 92.11 4.22 99.11<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda3 0.00 0.00 0.00 51.49 0.00 51.49 1.00 0.99 19.13 19.17 98.71<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda4 0.00 548.51 0.00 183.17 0.00 5497.03 30.01 19.98 112.62 5.38 98.61<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>drbd0 0.00 0.00 0.00 717.82 0.00 5742.57 8.00 1092.35 1621.75 1.38 99.11<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><p class=MsoNormal><span lang=EN-US>avg-cpu: %user %nice %system %iowait %steal %idle<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> 0.25 0.00 0.29 0.00 0.00 99.46<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>Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda 0.00 885.00 0.00 228.00 0.00 8498.00 37.27 26.45 112.99 4.39 100.10<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda3 0.00 0.00 0.00 50.00 0.00 50.00 1.00 0.99 19.70 19.86 99.30<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sda4 0.00 885.00 0.00 178.00 0.00 8448.00 47.46 25.46 139.20 5.59 99.50<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>drbd0 0.00 0.00 0.00 1060.00 0.00 8480.00 8.00 2345.33 1761.36 0.94 100.10<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US>Can I improve the performance of DRBD?<o:p></o:p></span></b></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>The following is my drbd.conf configration:<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>global {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # minor-count 64;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # dialog-refresh 5; # 5 seconds<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # disable-ip-verification;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> usage-count no;<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><p class=MsoNormal><span lang=EN-US>common {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>protocol C;<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>disk {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> on-io-error detach;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> #size 454G;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> no-disk-flushes;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> no-md-flushes;<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><p class=MsoNormal><span lang=EN-US>net {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> sndbuf-size 512k;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # timeout 60; # 6 seconds (unit = 0.1 seconds)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # connect-int 10; # 10 seconds (unit = 1 second)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # ping-int 10; # 10 seconds (unit = 1 second)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # ping-timeout 5; # 500 ms (unit = 0.1 seconds)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> max-buffers 8000;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> unplug-watermark 1024;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> max-epoch-size 8000;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # ko-count 4;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # allow-two-primaries;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> cram-hmac-alg "sha1";<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> shared-secret "hdhwXes23sYEhart8t";<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> after-sb-0pri disconnect;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> after-sb-1pri disconnect;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> after-sb-2pri disconnect;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> rr-conflict disconnect;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # data-integrity-alg "md5";<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> # no-tcp-cork;<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><p class=MsoNormal><span lang=EN-US>syncer {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> rate 120M;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> al-extents 517;<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><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>resource data {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> on mail1.domain.com {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> device /dev/drbd0;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> disk /dev/sda4;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> address 192.168.8.62:7788;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> meta-disk /dev/sda3 [0];<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><p class=MsoNormal><span lang=EN-US> on mail2.domain.com {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> device /dev/drbd0;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> disk /dev/sda4;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> address 192.168.8.63:7788;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> meta-disk /dev/sda3 [0];<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><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Please help me. Thanks.<o:p></o:p></span></p></div></body></html>