Read the manuals regarding garbage collection and sweeping. Sounds
like you are hitting an automated sweep of the db after roughly every
20,000 updates. Turn automated sweeps off (set to 0 instead of the
default 20,000) and try again.

Regards,
Andrew Ferguson
-- Proudly back-engineered from alien technology.

--- In ib-support@y..., "Adrian Roman" <aroman@r...> wrote:
> Two more things about this issue: the cpu% stays at 99%, and it's
almost all
> in user mode (kernel time is very low, under 1%).
> I tried just repeating the same update statement twice with the
same result
> (by the way, is FB keeping copies of "before" and "after" for data
from a
> record even in the case it's not actually modified?).
>
>
> Adrian Roman
>
> > I started an update wich modifies a field for all 30000 records.
It takes
> > only a couple of seconds. After that, without commiting the
transaction, I
> > change the update statement to change the same field on all
records, but
> > with a different value. This can take even 10 minutes to complete.
> Rollback
> > after that sometimes goes fast (several seconds), sometimes is
slow, but
> not
> > that slow as performing the update.