Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
just checking, 1) have you tested the throughput of your dedicated link ( I'm assuming you have DRBD setup to do sync writes ) 2) can you max out array throughput or link throughput ( whichever comes first ) by writing a large file to the drbd device ? Daniel Bourque Sr. Systems Engineer WeatherData Service Inc An Accuweather Company Tobias Appel wrote: > Hi all, > > I recently installed DRBD 8.0.14-23 on two RHEL5 machines for use with > heartbeat, mysql, apache and so on. > The two machines are Sun xfire4140 with two quadcore 2.3 ghz AMD > opterons, 8 GB RAM each and are directly connected via two crossover > cables on gigabit lan using interface bonding (so it should be like a 2 > gbit/s connection). > DRBD sits on a hardware raid 1 of two SAS harddrives. The drbd partition > is 75G in size. > > Now I have some trouble with my applications that use MySQL (which > resides on the DRBD) being extremely slow. > > My output from iostat suggests that the DRBD partition is very slow: > > Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz > avgqu-sz await svctm %util > sda 0.00 22.80 0.00 17.10 0.00 159.60 18.67 0.01 0.56 0.08 0.14 > drbd0 0.00 0.00 0.00 26.80 0.00 107.20 8.00 3.60 134.46 37.26 99.85 > > The question now is where can I start looking for the issue of this? How can I tune performance? > Are there any special options in the drbd.conf I should look out for? > > Thanks in advance, > Tobi > > this is the output from /proc/drbd: > version: 8.0.14 (api:86/proto:86) > GIT-hash: bb447522fc9a87d0069b7e14f0234911ebdab0f7 build by bachbuilder@, 2008-12-19 22:49:51 > 0: cs:Connected st:Primary/Secondary ds:UpToDate/UpToDate C r--- > ns:53981200 nr:1053428 dw:55034628 dr:154637 al:458 bm:208 lo:0 pe:2 ua:0 ap:1 > resync: used:0/61 hits:65688 misses:104 starving:0 dirty:0 changed:104 > act_log: used:1/257 hits:13494842 misses:464 starving:0 dirty:6 changed:458 > > > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user > > > >