Thread: Set priority for requests
Actually it seems impossible to set priorities to backends. But in a real database, which runs 24h / day, you might have to run batch programs that, for example, reads database to extract some data, but in parallel, you still have transactions which must be performed with good performance. Can we imagine that, in the future, it will be possible to set priority to backends allowing batch programs to run without giving penalty to interactive transactions ? Thanks for the best Open source DBMS ! Regards,
On Sat, Jul 07, 2001 at 11:10:56PM +0200, Laurent HERVE wrote: > Actually it seems impossible to set priorities to backends. But in a real > database, which runs 24h / day, you might have to run batch programs that, for > example, reads database to extract some data, but in parallel, you still have > transactions which must be performed with good performance. Can we imagine > that, in the future, it will be possible to set priority to backends allowing > batch programs to run without giving penalty to interactive transactions ? I'm not sure if I'm on the right track but this question comes up in various places to do with locking and priorities. If something is holding a lock but has a really low priority then other processes with a higher priority may get jammed. This may not be a problem with Postgres's not-really-locking model, but things are not as easy as they sound. -- Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/ > It would be nice if someone came up with a certification system that > actually separated those who can barely regurgitate what they crammed over > the last few weeks from those who command secret ninja networking powers.
On Wed, 11 Jul 2001, Martijn van Oosterhout wrote: > On Sat, Jul 07, 2001 at 11:10:56PM +0200, Laurent HERVE wrote: > > Actually it seems impossible to set priorities to backends. But in a real > > database, which runs 24h / day, you might have to run batch programs that, for > > example, reads database to extract some data, but in parallel, you still have > > transactions which must be performed with good performance. Can we imagine > > that, in the future, it will be possible to set priority to backends allowing > > batch programs to run without giving penalty to interactive transactions ? > > I'm not sure if I'm on the right track but this question comes up in various > places to do with locking and priorities. > > If something is holding a lock but has a really low priority then other > processes with a higher priority may get jammed. This may not be a problem > with Postgres's not-really-locking model, but things are not as easy as they > sound. I'm not sure if I'm on the right track either but assuming that the batch job you have is a file that you feed to psql froma cron job why don't you just make the specific process nice(1)er ? cheers, thalis > -- > Martijn van Oosterhout <kleptog@svana.org> > http://svana.org/kleptog/ > > It would be nice if someone came up with a certification system that > > actually separated those who can barely regurgitate what they crammed over > > the last few weeks from those who command secret ninja networking powers. > > ---------------------------(end of broadcast)--------------------------- > TIP 5: Have you checked our extensive FAQ? > > http://www.postgresql.org/users-lounge/docs/faq.html >