No, this is a single process. And there's known issues with context
storms on Xeons, so that might be what you're seeing.

On Tue, Apr 19, 2005 at 09:37:21PM -0700, Mischa Sandberg wrote:
> Quoting Tom Lane <[EMAIL PROTECTED]>: 
> > "Jim C. Nasby" <[EMAIL PROTECTED]> writes: 
> > > A friend of mine has an application where he's copying in 4000 rows at a 
> > > time into a table that has about 4M rows. Each row is 40-50 bytes. This 
> > > is taking 25 seconds on a dual PIII-1GHz with 1G of RAM and a 2 disk 
> > > SATA mirror, running FBSD 4.10-stable. There's one index on the table. 
> >  
> > If there's no hidden costs such as foreign key checks, that does seem 
> > pretty dang slow. 
> >  
> > > What's really odd is that neither the CPU or the disk are being 
> > > hammered. The box appears to be pretty idle; the postgresql proces is 
> > > using 4-5% CPU. 
> --  
> This sounds EXACTLY like my problem, if you make the box to a Xeon 2.4GHz, 
> 2GB 
> RAM ... with two SCSI drives (xlog and base); loading 10K rows of about 200 
> bytes each; takes about 20 secs at the best, and much longer at the worst. By 
> any chance does your friend have several client machines/processes trying to 
> mass-load rows at the same time? Or at least some other processes updating 
> that table in a bulkish way? What I get is low diskio, low cpu, even low 
> context-switches ... and I'm betting he should take a look at pg_locks. For 
> my 
> own problem, I gather that an exclusive lock is necessary while updating 
> indexes and heap, and the multiple processes doing the update can make that 
> pathological. 
> Anyway, have your friend check pg_locks. 
> "Dreams come true, not free." -- S.Sondheim, ITW 

Jim C. Nasby, Database Consultant               [EMAIL PROTECTED] 
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