Subject Re: Firebird slows after some Hours with 40+ Users
Author dimi1309 <>
--- In, Helen Borrie <helebor@t...> wrote:
> At 08:07 AM 10-12-02 +0000, Sven wrote:
> >Hi all,
> >
> >we┬┤ve got an app that slows extremly down with 20+ Users, the app is run=
> >
> >g 24/7, peak we have 50+ Users. CPU-Usage grows ap. 100 times and reques=
t go=
> >
> > from 2 sec to 40-60 sec. We replaced all "edit" Transactions with Memo=
> >
> >les, but there are still some "readonly"-Transactions. Replacing them wo=
uld =
> >
> >blowup the Client. We are using Delphi6 with IBX. Between OIT and OAT ar=
e ap=
> >
> > 15000 till 20000. The Server is a Dual-P3 600 MHz with 1 GB Ram with W=
> >
> >0 Server, CPU-Affinity is set to 1.
> >
> >Anyone got an idea?
> If the app is slowing down and the Oldest Transaction isn't moving forwar=
> then it's a sure sign that your app has long-running transactions that ar=
> inhibiting garbage collection. See the previous thread "Re: Problem with=

> growing database" as the issues raised and solved there apply to your
> problem as well.
> It's not a question of how many users are connected, but how many users a=
> connected and running long transactions.
> Read-only transactions won't inhibit garbage collection. I doubt that
> "replacing all "edit" Transactions with Memorytables" would have helped
> anything. A table is not a transaction. The problem may have more to do=

> with using CommitRetaining in all cases, and never performing any hard
> Commits to keep the garbage levels low.

this is after the replacing:
Oldest transaction 16209
Oldest active 16210
Oldest snapshot 16210
Next transaction 34332
the performance is still a disaster.
a manual sweep after disconnecting all users showed also no effect.
we needed to restart the firebird-service, but backup and restore shows bet=
ter/longer effect

is it possible to use db-components after committing the transaction?

> Using table components will kill performance - they are not designed for =

> client/server databases and should be avoided.

thats clear, but our users leave apps for hours in "edit mode"