Subject RE: [***SPAM*** Score/Req: 5.4/4.0] [firebird-support] Re: GBAK Backup Size
Author Andrew Stuart
Problem is we're a 24/7 company and it takes a while to scedule reboots of certain critical systems

any ideas what sort of performance issues with the GDB?

i did delete the exisiting backup and watched it backup again, still was 2gig more than current FDB
Also all the DB's on that server only make up 2.4GB, which is still a gig less than the main DB's FBU ;\

ill have to see if i can scedule a restart of the service or something, i dont quite know how to release all the handles? if thats just a case of no users being connected, we'd never have that situation occur in normal business use.

Cheers for pointers so far


From: on behalf of Adam
Sent: Thu 17/07/2008 00:15
Subject: [***SPAM*** Score/Req: 5.4/4.0] [firebird-support] Re: GBAK Backup Size

--- 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.


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