Subject Re: GBAK Backup Size
Author Adam
--- In, "call.assist"
<Andrew.Stuart@...> wrote:
> Hi
> (prob doing something stupid here, but hey ho)
> I've a couple of different DB/Servers running gbak regulary
> I've noticed one has a GDB file size of 1.5gig, and GBK produced is ~
> 1.5GB

Don't use GDB file extension on Windows. Irrelevant to your problem
but will cause other performance issues.

> Another has a CABS FDB of 1.5Gig and produces a FBU of around 3.5GB
> both use exactly the same gbak command line , within reason.
> "D:\Program Files\Firebird_1_5\bin\gbak" -backup -user SYSDBA -
> password xxx -nt localhost:e:\Data\DB.fdb e:\Backup\DB.FBU
> any ideas?

In my experience, the backup file is always smaller than the database.
This makes sense, because the database file will contain deleted data
awaiting garbage collection as well as indices, whereas the backup
file only contains the index definition and obviously no deleted data.

Have you shutdown the Firebird service after making the backup?
Remember explorer doesn't always update the displayed file sizes in an
expected manner, so your database file may actually be larger that
1.5GB. You don't necessarily need to shut down the service, but
releasing all the handles to the gdb file will probably trigger it to
refresh the file size.

The only other flag I can see there it the non transportable backup,
meaning you won't be able to restore it on some non x86 architectures,
but I don't see how that would increase file size.