Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Forgot to mention, DRBD version is 0.7.11. Weilin Gong wrote: > Hi, > > I ran some drbd performance tests with 'tiobench': > > tiobench.pl --identifier drbd-connected --size 5000 --numruns 1 --dir > /secroot --block 4096 --threads 4 > > noticed the huge max latency numbers with Sequential Writes: > > Unit information > ================ > File size = megabytes > Blk Size = bytes > Rate = megabytes per second > CPU% = percentage of CPU used during the test > Latency = milliseconds > Lat% = percent of requests that took longer than X seconds > CPU Eff = Rate divided by CPU% - throughput per cpu load > > Identifier > > > > File Size > > > > Blk Size > > > > Num Thr > > > > Rate > > > > Maximum CPU% > > > > Avg Latency > > > > Max Latency > > > > Lat% >2s > > > > Lat% >10s > > > > CPU Eff > > Raw-device > > > > 5000 > > > > 4096 > > > > 4 > > > > 31.24 > > > > 26.80% > > > > 0.364 > > > > 5635.06 > > > > 0.00242 > > > > 0.00000 > > > > 117 > > Drbd-disconnected > > > > 5000 > > > > 4096 > > > > 4 > > > > 33.18 > > > > 26.29% > > > > 0.319 > > > > 110394.58 > > > > 0.00190 > > > > 0.00016 > > > > 126 > > Drbd-connected > > > > 5000 > > > > 4096 > > > > 4 > > > > 20.88 > > > > 50.18% > > > > 0.457 > > > > 135712.09 > > > > 0.00110 > > > > 0.00008 > > > > 42 > > > My lab setting: > > * Two Linux nodes on 2.6.10_mvlcge401-pc_target-x86_pentium3-P3SMP. > * Dual-core Intel Xeon 2GHz CPU, 4GB Memory, 1Gbits/s network > interface. > * 5.7GB partition on SCSI disk, ext2 file system with the "-T > largefile4" option. > * DRBD rate=100M; protocal C; sndbuf-size 1024k. > > I don't believe the disk (~50MB/s) or network may be the factors here. > You can see the big number jump even with the DRBD disconnected mode. > > Any help on analyzing/identifying the problem will be greatly appreciated. > > Weilin > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20070105/1d3d9da9/attachment.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: wgong.vcf Type: text/x-vcard Size: 126 bytes Desc: not available URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20070105/1d3d9da9/attachment.vcf>