Subject RE: [firebird-support] nbackup / gbak interoperation
Author Alan McDonald
> Since nbackup locks a db and causes a delta file to be created and
> written to for the duration of the file lock, would it be
> possible/feasible in an OLTP environment to:
>
> Lock a file using nbackup
>
> Backup the file using gbak
>
> Restore the file using gbak, overwriting the original file
>
> Unlock the file using nbackup, causing the delta file to be merged
>
> ???
>
> I'm thinking this would be a way to reclaim lost space in an OLTP
> system's db file without kicking off the users during the backup and
> without losing any data.
>
> How much load can this delta file handle? How long does it take to
> merge back x amount of data in a delta? When the transition from main
> file to delta takes place, are there any hiccups/delays, or is it
> completely transparent to the system performance?
>
> Thanks for any responses.
>
> David Keith

I wonder how nbackup is going to handle the delta file creation during the
overwriting of the original file? How will it know what a delta is?
Alan