Re: Large database help

On Sun, Apr 22, 2001 at 06:52:26PM -0400, xbdelacour@yahoo.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