Re: Large database help

On Sun, Apr 22, 2001 at 06:52:26PM -0400, xbdelacour(at)yahoo(dot)com wrote:
> I'm spawning 6 backends to query the data. top lists 6 postmaster processes
> working, and therefore the idle time should hit 0% easily. Also, the hard
> drive light goes nuts when I'm running this.
>
> Here is the pertinent information from top. To be clear, I'm NOT spawning a
> new postmaster per chunk. These same six processes are alive and kicking
> for over 4 minutes.
>
> I hope the formatting works ok.
>
> PID USER PRI NI SIZE RSS SHARE STAT LIB %CPU %MEM TIME COMMAND
> 2379 mg 13 0 14476 14M 12908 S 0 5.8 2.7 0:01 postmaster
> 2380 mg 10 0 14436 14M 12868 S 0 2.9 2.7 0:01 postmaster
> 2381 mg 10 0 13572 13M 12012 S 0 2.9 2.6 0:00 postmaster
> 2377 mg 10 0 13640 13M 12072 S 0 2.4 2.6 0:01 postmaster
> 2378 mg 11 0 14476 14M 12908 S 0 2.4 2.7 0:01 postmaster
> 2376 mg 8 0 13556 13M 11984 S 0 1.9 2.6 0:00 postmaster

The processes should have ~ 400M shared memory, not ~ 10M, right?
stracing (or maybe just running with debugging enabled) should tell you
what went wrong. My first guess is that the OS is not able to provide a
single 400M block of memory, and postgres falls back to some lower
setting.

You could also verify this by writing a small program that just
allocates different sizes of shared memory, and see what the biggest
size you can allocate is.

--
Ragnar Kjørstad