Re: Expectations of MEM requirements for a DB with large tables.

Mike,

> Anyway, I crashed my system the other day when I did a "select *" from
> one
> of my large tables (about 5.5gb in size).

Well.... It takes abit more than that to actually crash the system. Can
you give more details? What _exactly_ happened? Did it hang? Kernel
panicked? Something else.

> Does anyone know what the ratio of data output size (say from a select)
> to
> the amount of
> RAM used is?

It simply can't be other than 1 : 1. Well, in a sense. Did you use psql?
Other app? If the latter, what interface: API, DBI, other? Was it a local
or remote request?

> Other relevant info, RedHat Linux 2.2.17 kernel, PostgreSQL 7.0.2.

Is this a genuine kernel, or the one shipped by RH? Did you build PGSQL
from sources or was it a pre-built binary? How much RAM do you have, how
fast and big is your swap? Swap settings? Other processes running?
As you see, there are more questions than answers at this stage. Tell us
more. Tuning the system has never been easy.