Subject Re: garbage collect in backup
Author c_pradelli
Thank you very much Ann,

One more question,
I have a database, it size it is about 5 GB and it usually have about
30 active connection with heavy load, I need to do 2 backups over the
day.
If I do the backup with the -g switch would be impact less in server
performance than without it?

Best regards
Christian

""Ann W. Harrison"" <aharrison@...> escribió en el mensaje
news:42CEB9C6.7060706@......
> c_pradelli wrote:
>>
>> I have got some question about garbage collect and gbak:
>>
>> What is the benefit of do a garbage_collect on the database when
I'm
>> doing a backup with gbak?
>
> If you plan to replace the database with one restored from the
backup,
> there's no benefit. If not, then removing unneeded back versions
of
> records will improve performance by limiting the growth of the
database
> and by avoiding the cost of garbage collection when the database is
more
> heavily used.
>
>> Are there any difference in the backup file that I obtain from gbak
>> if I use the -g[arbage_collect] switch or if I don't use it?
>
> None.
>
>> Why garbage_collect is enabled by default in gbak if there are
other
>> tools (gfix) for doing that explicitly?.
>
> Garbage collection is enabled by default on all functions of the
> database - all transactions, including read-only transactions
either
> perform garbage collection or produce lists of work for a separate
> garbage collection thread. It's just good housekeeping - life is
more
> pleasant if you clean up messes as you find them rather than
waiting
> until the mess is intolerable, then stopping everything and doing a
> massive cleanup.