Re: "set nice" running a transaction in a lower priority?

Richard Huxton <dev@archonet.com> writes:
> On Wednesday 12 Jun 2002 6:33 pm, Clark C . Evans wrote:
>> I was wondering if there is a way to set transaction
>> priority so that it takes its good sweet time and
>> handles other queries quickly?

> Not really - and it might be counter-productive to slow down the import. If
> another transaction can't complete until the import is finished then
> everything could end up delayed.

> I guess you could nice the pid of the relevant backend process,

That would be a bad idea for the same reason --- you'd get into
priority-inversion scenarios where foreground processes are waiting for
the low-priority process, which can't run because other foreground
processes are hogging all the CPU.

> but I'd be
> inclined to batch the import into sections of 5000 records or so and sleep
> for a second between batches.

Some kind of throttle on the client side seems like a better idea to me
too.

            regards, tom lane