Re: How to improve archive performance

Agostino Brunamontini wrote: > > Hi, > > I need to backup an OnLine (version 5.0) with large databases. > The OnLine does not use transaction logging. > Because an archive does not fit in one tape it is necessary to do the > archive when someone is at the console and can change the tape. > I was thinking in doing an archive (level 0) just once and after that > during the night (from contrab) run a tbunload of each database that can > fit in one tape. > Is that right? What would happened in case of a system crash? > I mean, can I restore the entire system using the level 0 archive > plus the tbunloads? > > The tables in the databases are heavily used so an incremental backup > would take several tapes as well. > > Thank you very much. > > Please e-mail to me. > > Agostino Brunamontini > SRD. Italy. > abrunamontini@srd.it If the database is so heavily used is there a timeslot in which you could obtain a consistent set of unloads? If not your database would be inconsistent after a restore. If you can find a higher capacity tape which will take incrementals without a tape change this would be best. An alternative might be to find a way of monitoring the tape. HP-UX systems come with a utility called "monitor" which lets you, amongst other things, view the amount of I/O on each file descriptor of a running process. We quickly worked out which was the tape drive and then ran this in a window during each archive. Just before the tape filled up the operator would have to jump up, sprint across the office and get to the computer room in time to change the tape. If your platform is HP-UX, check this one out. I think monitor is an HP specific tool. someone out there might know of somethin in the public domain. Ian