Hi, Klaus: Thank you very much for your kind answer. Tunning the parameters sounds really interesting. I should give it a try. By the way, how did you come up with these new parameter values? Did you calculate them based on some measures or simply pick them up and test. Best, Jas --- Klaus Steinberger <Klaus.Steinberger@xxxxxxxxxxxxxxxxxxxxxx> wrote: > Hi, > > > However, it took ages to list the subdirectory on > an > > absolute idle cluster node. See below: > > > > # time ls -la | wc -l > > 31767 > > > > real 3m5.249s > > user 0m0.628s > > sys 0m5.137s > > > > There are about 3 minutes spent on somewhere. Does > > anyone have any clue what the system was waiting > for? > > Did you tune glock's? I found that it's very > important for performance of > GFS. > > I'm doing the following tunings currently: > > gfs_tool settune /export/data/etp quota_account 0 > gfs_tool settune /export/data/etp glock_purge 50 > gfs_tool settune /export/data/etp demote_secs 200 > gfs_tool settune /export/data/etp statfs_fast 1 > > Switch off quota off course only if you don't need > it. All this tunings have > to be done every time after mounting, so do it in a > init.d script running > after GFS mount, and of course do it on every node. > > Here is the link to the glock paper: > > http://people.redhat.com/wcheng/Patches/GFS/readme.gfs_glock_trimming.R4 > > The glock tuning (glock_purge and demote_secs > parameters) definitly solved a > problem we had here with the Tivoli Backup Client. > Before it was running for > days and sometimes even did give up. We observed > heavy lock traffic. > > After changing the glock parameters times for the > backup did go down > dramatically, we now can run a Incremental Backup on > a 4 TByte filesystem in > under 4 hours. So give it a try. > > There is some more tuning, which could be done > unfortunately just on creation > of filesystem. The default number of Resource Groups > is ways too large for > nowadays TByte Filesystems. > > Sincerly, > Klaus > > > -- > Klaus Steinberger Beschleunigerlaboratorium > Phone: (+49 89)289 14287 Am Coulombwall 6, D-85748 > Garching, Germany > FAX: (+49 89)289 14280 EMail: > Klaus.Steinberger@xxxxxxxxxxxxxxxxxxxxxx > URL: > http://www.physik.uni-muenchen.de/~Klaus.Steinberger/ > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
