Re: low priority postmaster threads?

Chris Storah <cstorah@emis-support.demon.co.uk> writes:
> Is there any way in psql to connect to a database and reduce the run
> priority of the child thread it kicks off ?
> i.e. equivalent of 'nice' on the thread?

Not at the moment, though it'd be a fairly trivial hack on postgres.c
to add a "-nice n" backend switch, which you could then specify at
connection time via PGOPTIONS.

> What I am looking for is a postgres system that runs 100 users or so at
> 'full speed', and major day long queries at a 'when idle' priority.

The trouble here is that CPU nice doesn't (on most platforms) change the
behavior of the I/O scheduler, so this would only be of use to the
extent that your queries are CPU bound and not I/O bound.
        regards, tom lane