Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
De:drbd-user-bounces at lists.linbit.com Para:"drbd-user" drbd-user at lists.linbit.com Cópia: Data:Thu, 23 Sep 2004 15:09:37 +0200 Assunto:Re: [DRBD-user] drbd tranfer limitations (random and sequential acccess) using raw > / 2004-09-23 09:47:48 -0300 > \ crsurf: > > > / 2004-09-23 09:01:50 -0300 > > > \ crsurf: > > > > Hello list > > > > I?m using drbd in a Gigabit network (crossover cable) and when I > > > > synchronize data (sequential read/write) the tranfer hit to 30~40 > > > > Mb/s, but when I make inserts into database (random read/write) that > > > > access drbd device via raw, the transfer rate hit only 5~6 Mb/s. > > > > Exists some way to improve this performance? I increased the > > > > sndbuf-size to 256K, but no such effect. I increase interface MTU to > > > > 9000 and no such effect too. One database process that run in 4 min. > > > > without replication, run in 30 min. with replication. Now I?m trying > > > > using filesystem jfs instead raw to view if the performance will be > > > > improved. > > > > Maybe sync-nice can help us? > > > > > > I am not sure which transfer rate you are talking about. > > > the throughput of your applications, or the resync throughput? > > > > > > > With resync tha transfer hit 40~50 Mb/s, afer I changed MTU. > > > > > or the resync throughput while you have resynchronization and > > > applications running concurrently? > > > > > > > And when I make a insert into database the transfer hit to 4~6 Mb/s, > > without full synchronization, only online synchronization. > > which transfer. > sorry, again I don't get you here. > > is it that your data base has a write throughput of 6 MB, > or that drbd resync throughput drops to 6 MB while the database is > running? Yes is it, when using database throughput not pass 6 Mb/s. > > how do you measure? I´m using iptraf to view network traffic and is that wich says the throughput I mencioned before (4~6 Mb when inserting in database and 40~50 Mb/s when doing SyncingAll). This is the output of iostat on primary server avg-cpu: %user %nice %sys %iowait %idle 0.79 0.00 1.54 3.28 94.39 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sda 120.44 5271.05 1872.72 290326040 103148100 sda1 0.00 0.05 0.01 2928 424 sda2 120.43 5271.00 1872.71 290323088 103147676 This is the output of iostat on seconday server avg-cpu: %user %nice %sys %iowait %idle 0.32 0.00 1.82 3.58 94.27 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sda 212.38 1159.70 6143.03 84933272 449898916 sda1 0.00 0.02 0.01 1736 416 sda2 212.38 1159.67 6143.02 84931456 449898500 > > and if you are concerned about your database application throughput, > how does it compare to the figures you get when not using drbd? When using drbd connected to secondary the time of an process is 20~30 min. When using with drbd disconnect to secondary the time is 4~5 min. On primary server I have a RAID 10 (0+1) and on secondary server I have only one disk SCSI. Maybe this causing delay too? > > > > and when you talk about sync-nice, you are using drbd 0.6 ? > > > > Yes, I?m using 0.6.13 > > > > > > > > maybe you want to use 0.7 instead. it reduces the amount of data > > > transfered to a minimum, thus reducing the time for resynchronization to > > > some one to three minutes, typically. > > > > Well, I?m already compiled 0.7.4, but my question is: I can use the > > config file of 0.6 in 0.7? And the drbdsetup commands to replicate and > > define primary node are the same? > > you have to adopt the conf file, syntax has changed. > should be easy enough. > though, make sure you first read > upgrade_0.6.x_to_0.7.0.txt and > upgrade_0.7.0_to_0.7.1.txt > > I don't understand what you mean by "commands to replicate". > in general, the interface for 0.7 is the new drbdadm command, > and it has a nice little english manpage that should even be complete. > Tanks in advance > > Lars Ellenberg > > -- > please use the "List-Reply" function of your email client. > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user > > Esta mensagem foi verificada pelo E-mail Protegido Terra. > Scan engine: VirusScan / Atualizado em 22/09/2004 / Vers?o: 1.5.2 > Proteja o seu e-mail Terra: http://www.emailprotegido.terra.com.br/ > > E-mail classificado pelo Identificador de Spam Inteligente Terra. > Para alterar a categoria classificada, visite > http://www.terra.com.br/centralunificada/emailprotegido/imail/imail.cgi?+_u=crsurf&_l=1095944996.747869.15443.gravatal.terra.com.br > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20040923/0e47bc80/attachment.htm>