On Wed, 8 Jul 2015 12:14:13 +0000, "Svein Erling Tysvær
svein.erling.tysvaer@... [firebird-support]"
<firebird-support@yahoogroups.com> wrote:

> Take a look here: http://www.firebirdfaq.org/faq361/
>
> I'd add that restore also has a -use_all_space option. If you don't
> specify this, then pages are filled to approximately 80% (80% is

preferable

> over 100% unless it is a read-only database). See
> http://www.firebirdsql.org/manual/gbak-cmdline.html or
> http://www.firebirdsql.org/manual/gfix-pagespace.html for more

information.

Another reason could be restoring with a different page size than the
original database.

Mark