Optimization

Greetings,

I am trying to understand the various factors used by Postgres to optimize. I presently have a dual-866 Dell server with 1GB of memory. I've done the following:

set /proc/sys/kernel/shmmax to 512000000
shared_buffers = 32000
sort_mem = 32000
max_connections=64
fsync=false

Can someone tell me what effective_cache_size should be set to? what kind of formula to use for this? (I got the other figures from phpbuilder.com, and modified for 512k memory).

The databases I'm using have about 200,000+ news headlines with full-text indexes (which range upwards of a few million records). They are updated about every 5 to 10 minutes, which means I also have to run a vacuum about once every 2 to 3 hours at least. As I get more updates obviously the efficiency goes down. I'm trying to make the most of this system but don't fully understand PG's optimization stuff.

Thanks in advance,
Justin Long