adrien ducos <aducos(at)hbs-research(dot)com> wrote:
[rearranged somewhat]
> The version of both databases is postgres 8.4.1
[sigh] You really should upgrade.
http://www.postgresql.org/support/versioning
http://www.postgresql.org/docs/8.4/static/release.html
> So I checked the memory on prod during my query execution:
> vmstat
> procs -----------memory----------
> r b swpd free buff cache
> 0 1 1280 23320 6356 2975956
> The swap is not used but something is a bit odd: the cache is
> using 98% of the RAM
The first line in vmstat (which is all you get if you run it without
a number) is averages since the OS was booted. That's not usually
very helpful. What does this show?:
free -m
or run the query while watching the output from:
vmstat 1
> the copy of files on the SAN is about 3 times faster than on the
> development hard drive.
Copy time doesn't always correlate real well with database
performance. Have you tried running bonnie++ or similar?
-Kevin