I agree with the DSU suggestion -- this is exactly the reason we use that method with an Informix DB here. Waiting for tape to do these backups just isn't fast enough. The DSU solves this problem completely.
-----Original Message----- From: veritas-bu-boun...@mailman.eng.auburn.edu [mailto:veritas-bu-boun...@mailman.eng.auburn.edu] On Behalf Of Justin Piszcz Sent: Friday, March 27, 2009 4:48 PM To: Larry Mascarenhas Cc: veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] Slow Informix Logs backups On Fri, 27 Mar 2009, Larry Mascarenhas wrote: > Hello, > > I'm running backups on Informix7 DBs. We're able to stream the DB > backups using parallelism 4 and get good throughput (100MB/s, yes > megabytes/sec, it is a SAN Media Server). A 300Gig DB takes less than 1 > hour. > > However (I know ;)), when it backs up the LOGS (all backups go to tape, > I don't have Disk backups), each log comes in as a separate request. > Each log is therefore a separate job. So the time taken to process this > request is greater than the time to backup each log. ie each log is > 100MB and the time taken is <2secs (when the resource is allocted and > ready), but it takes 1+min to create the job/assign the resource/and > begin writing. This is resulting in my never being able to catch up with > the rate of logs generation although the amount to be backed up is > minimal eg 30logs is just 3Gig, but takes approx 30mins and by that time > 10 more logs are created. I am using media_unmount_delay so the tapes > are not re-mounting for every request. > > I cannot increase the size of the LOGS as this would affect replication > and recoverability (double whammy). This is Symantec's recommendation. > > I'm looking for experiences that people have had to speed up the > Informix backups. > > Thanks. > > -- > > Larry Mascarenhas > lmasc...@comcast.net > _______________________________________________ > Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu > Why not use a Disk Staging Unit if the logs are small enough? Send to disk first -----> then shoot to tape? Justin. _______________________________________________ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu _______________________________________________ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu