Subject Re: [firebird-support] Re: Firebird Hanging
Author Ann W. Harrison
> A better sequence is sweep, then backup :)
>
> Cool - thanks. I'll go change that right now.
>

Actually, it doesn't make much difference. If you
do the sweep first, then the backup doesn't have to
do any garbage collection - except for new versions
created after the sweep started and before the
backup started. If you do the backup first, then
there aren't any old versions for the sweep to sweep
up - except new versions created after the backup
started and before the sweep started. There is a
(very slight) advantage to running the sweep after
the backup - sweep changes the value of the oldest
interesting transaction and it will get a higher
value if it runs later. If you sweep first, then
backup, then the backup will be faster... by about
the same amount as the sweep is slower.

What does make a huge difference is to skip the
sweep and run gbak with the -g when you know you're
going to restore the backup immediately and replace
the database with the new version when the restore
completes.

Cheers,


Ann