>>>"D'Arcy J.M. Cain" said:> On Thursday 16 January 2003 11:59, Adrian 'Dagurashibanipal' von Bidder wrot e:> > On
Thu,2003-01-16 at 17:42, D'Arcy J.M. Cain wrote:> > > We are also looking at hardware solutions, multi-CPU PCs with
tons(24GB )> > > of memory. I know that memory will improve access if it prevents> > > swapping but how well does
PostgreSQLutilize multiple CPUs?> >> > At most one CPU is used for any single postgres backend (that means for> > any
singledatabase connection). So, if your load problem is single> > queries being too slow, thee's nothing you can do
withadding more CPUs.> > If your problem is many connections maxing out the db, PostgreSQL can> > take full advantage
ofmultiple CPUs.> > I most definitely have multiple queries running at once. My main issue is > whether PostgreSQL
scalesup properly or does it get bogged down with too > many locked queries.
That would depend on the OS. Not many 'pc-based unix' support over 4 GB of
memory, some don't even go that far.
If memory is an issue, have you considered going to 64bit CPU?
Memory is indeed an issue for a complex database setup, especially if you want
to give the backends enough shared and sort memory.
As already said, PostgreSQL will utilize multiple CPUs - as effectively as
your OS can do this of course. PostgreSQL is not an OS by itself and does not
really control these resources.
I have also found it very helpful to split database from application servers
(wish I do it as often as I recommend it :) - thus you can optimize the part
that needs most resources.. In many cases the requirements are quite
different. With todays gigabit LANs, bandwidth between machines shouldn't be
an issue.
By the way, I too wonder which supported OS platform would support over 4GB of
memory on a PC..
Daniel