Tim,

I was with you on this (I hadn't considered all the transactions,
etc. that were covered by the recovery log) until the last
sentence, b/c you just described our environment. We do a
full database backup every day. I'm running on a wide node SP2
with 256MB of ram, and am connected to three 3590s (each on their
own SCSI bus).

We seem to get through about 5-6 hours of the nightly schedule
before triggering a database backup.

 -- Tom

> Date:    Wed, 5 Mar 1997 14:47:30 -0500
> From:    "Pittson, Timothy ,HiServ/US" <tpittson AT HIMAIL.HCC DOT COM>
> Subject: FW: Recovery log
>
> Tom,
>
>         When running in 'roll-forward recovery' mode, the recovery log tracks
> all transactions since the last database backup - this significantly
> increases the recovery log storage requirements.  Database growth will
> certainly contribute to this but keep in mind that database transactions
> also incrlude client backups/archives and 'background' processing such
> as migrations, reclamations, expiration processing, etc.. What you're
> seeing in your environment isn't out of line with what I saw when
> running in roll forward mode - our database was about 7 GB and I had to
> increase our recovery log from 600 MB to about 3 GB (dbbackuptrigger set
> to 80%)  to avoid database backups being triggered while the incremental
> backups were running.  Since migrating to an RS/6000 and fast tape
> drives, I've given up on this method and have gone to full database
> backups every day since they only take 45-50 minutes.
>
> Tim Pittson
> tpittson AT himail.hcc DOT com