Re: ontape vs onbar

I did some short tests to backup 600MB data (1 dbspace) with onbar/ism and ontape. Used onconfig.std except TAPEBLK 1024. 1. Debian Linux 3.1, 4 x Pentium3 900MHz, 4GB RAM: time onbar -b -L 0 0.55user 6.27system 0:15.02elapsed 45%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+8110minor)pagefaults 0swaps time ontape.sh (echo | ontape -s -L 0) 0.16user 6.24system 0:24.77elapsed 25%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+7817minor)pagefaults 0swaps 2. SuSE Linux 9.3, 1 x Pentium4 2GHz, 1GB RAM: onbar -b -L 0real 0m49.171s user 0m1.026s sys 0m1.945s time ontape.sh (echo | ontape -s -L 0) real 0m31.323s user 0m0.112s sys 0m2.765s Obviously in my example onbar/ism performes better on the SMP machine: 15.02s to 24.77s with ontape. See also 45%CPU onbar to 25%CPU ontape. Onbar CPU load was higher to complete earlier. The 'top' utility showed 1 oninit and 1 nsrmmd (from ism) each on 1 CPU with 99% load. Andreas On Thursday 11 August 2005 23:02, Neil Truby wrote: > IDS 10.0FC3 on Solaris 9 > > I'm doing some backups to disk. > > An ontape backup of the 30G database with a 768k TAPEBLK takes about 25 > mins, but an onbar -b -L 0 takes over twice as long. > > I wonder if it's that the block size being used is much smaller? There's > some excellent documentation in the DB2 Information Center, but this > doesn;t seem to be configurable. > > Also, it's writing out 15 x 2Gbyte files (sequentially) rather than one > large file: thought this would be different post-9.40. Anyone know why? > > Thanks > Neil sending to informix-list