Max amount of usefull RAM

Hi

i'm specing out a server for a postgres DB at work,
The DB is about 8 gig in size and about 90 Colums

I was looking at about 16 gig of ram, but i was wondering if Postgres can handle this amount of ram?

For compleetness the CPU's will be 2 Quad cores
and the server will be a dell 2950

greetz

Coro

Postgres does not really use the entire memory. It relies heavily on the filesystem to cache frequently accessed files.

You can increase some of the parameters for the internal memory that postgres still needs to improve performance, see:
http://www.postgresql.org/docs/current/static/runtime-config-resource.html

In general: the more RAM you have the more disk reads can be cached by the filesystem and thus PG will benefit from it.

It's ususally not necessary allocate as much as possible for Postgres.

This has been discussed several times on the mailing list. You might want to search the archives at:
http://www.nabble.com/PostgreSQL-f759.html
especially:
http://www.nabble.com/PostgreSQL---performance-f774.html

Edit: these threads might be of interest:
http://www.nabble.com/Planning-a-new-server---help-needed-td16348547.html
http://www.nabble.com/postgresql-is-slow-with-larger-table-even-it-is-in-RAM-td16270968.html

You should also pay close attention to your harddisk system. It affects performance nearly as much as memory!

SO if i understand correctly, (cause i'm new to postgres and DB maintenance in general)


if my current server is using about 5 gig of ram (of the available 6) , it would be pointless to stick more than, lets say 8gig, in the new server ?

You should start by reading the sticky "performance resources" on top of this forum, without proper config tuning memory will rest unused with every database

No, it wouldn't be pointless.
Just don't assign all that memory to PostgreSQL's shared buffers or whatever.
Simply trust the filesystem that it will use the memory for a file cache.

(And of course do follow pabloj's suggestion)