> I'm trying to track down an intermittent performance issue, and I find I
> don't have sufficient grasp of sweep behavior.
>
> firebird 2.1.5 classic on centos
>
> I understand that a sweep is started (new thread is created) when OST-OIT >
> 20000 (by default). What I can't find documented is when this check is
> made. Is it made when a client starts a connection, starts a transaction,
> queries a table or something else?

Dmitry, Vlad, Alex, Ann etc. have more insights here, but AFAIK with
each transaction start, TIP related stuff is processed/evaluated, thus I
guess the check happens upon a new transaction start, but I might be wrong.


Regards,
Thomas