At 04:51 PM 12/02/2009, you wrote:

>Hi,
>
>I developed a program using Delphi and I'm accessing a database of
>4Gb. My program can access the database without any problem except
>that, for an unknown reason, sometimes it is very slow and my program
>seam to stop responding.
>
>So, I thought that the database could be damaged or needed to be
>defragmented. So, I decided to do a backup/restore using gbak.
>However, when I try to backup the database, the gbak process never
>end. I alo tried the gfix utility with the same problem. It can run
>for hours without finishing. Usually, when I backup this database, it
>tkes only 10 to 15 minutes.
>
>So, is it mean that the database is corrupt?

Not necessarily. You could have a vast amount of garbage. If you don't plan to keep using the old database afterwards, try using the -g switch when doing the backup - that will prevent the program from performing garbage collection.

If you intend to restore, then make sure you do NOT use the -r[eplace_database] switch.

>What is strange is that I can access this database using my program.

Yes, it does sound like the typical Delphi scenario, where applications cause enormous amounts of garbage to build up, making performance slower and slower. Until and unless you are willing to fix up the application program(s) you're really stuck with doing frequent housekeeping.

./heLen