Re: postgresql and smp linux kernel

zhicheng wang <wang_zc(at)yahoo(dot)co(dot)uk> wrote:

> Thanks Oliver Elphick
> does this mean that the applications do not need to be
> multi-threading in order to use multi-processors?

Yes, that's what it means. Although you've probably oversimplified it
too much. Multi-process applications make use of multiple processors
just as well as multi-threaded apps do.

> --- Oliver Elphick <olly(at)lfix(dot)co(dot)uk> wrote:
> > On Mon, 2004-08-09 at 11:10, zhicheng wang wrote:
> > > Dear all
> > >
> > > i have a dedicated server mainly running
> > postgresql,
> > > currently rh-posgtresql-7.3.6.7 (and samba, ypbind
> > > etc). The server is a dual processor machine and
> > the
> > > OS is RHEL AS 3.
> > >
> > > I am currently running
> > kernel-smp-2.4.21-15.0.4.EL.
> > >
> > > My question is: do i need to run smp kernel for
> > > postgresql? What is benefit of it? If I run UP
> > kernel,
> > > what do I lose from the point view of PG?
> >
> > You do not NEED it for Pg, but it will improve
> > performance. Each
> > separate session gets a different process and
> > therefore has a change to
> > run on the second processor concurrently with
> > another session on the
> > first processor. The same goes for any other
> > processes that are
> > running, of course.
> >
> > If you do not use an SMP kernel, one of your
> > processors will sit there
> > for ever doing nothing, which is money down the
> > drain.
> >
> > --
> > Oliver Elphick
> > olly(at)lfix(dot)co(dot)uk
> > Isle of Wight
> > http://www.lfix.co.uk/oliver
> > GPG: 1024D/A54310EA 92C8 39E7 280E 3631 3F0E 1EC0
> > 5664 7A2F A543 10EA
> >
> > ========================================
> > "Be still before the LORD and wait patiently
> > for him;
> > do not fret when men succeed in their ways,
> > when they
> > carry out their wicked schemes."
> > Psalms 37:7
> >
> >
> > ---------------------------(end of
> > broadcast)---------------------------
> > TIP 5: Have you checked our extensive FAQ?
> >
> >
> > http://www.postgresql.org/docs/faqs/FAQ.html
> >
> >
>
> =====
> Best wishes
> Z C Wang
>
>
>
>
>
> ___________________________________________________________ALL-NEW Yahoo! Messenger - all new features - even more fun! http://uk.messenger.yahoo.com
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster

--
Bill Moran
Potential Technologies
http://www.potentialtech.com