Re: Determining server load from client

["Craig A. James" <cjames(at)modgraph-usa(dot)com>]

Dan Harris wrote:
> I've found that it would be helpful to be able to tell how busy my 
> dedicated PG server is ...
>
> I have seen some other nice back-end things exposed through PG functions 
> ( e.g. database size on disk ) and wondered if there was anything 
> applicable to this.

I'd write a simple pg-perl function to do this.  You can access operating-system calls to find out the system's load.  But notice that you need "Untrusted Perl" to do this, so you can only do it on a system where you trust every application that connects to your database.  Something like this:

create or replace function get_stats()
 returns text as '
 open(STAT, "</proc/stat");
 my @stats = <STAT>;
 close STAT;
 return join("", @stats);
' language plperlu;

See http://www.postgresql.org/docs/8.1/interactive/plperl-trusted.html

Craig