Optimization for 256 MB of ram server running apache/postgresql

Question

Hi,
I'm on a VPS for 256 MB of ram planning to run Apache and PostgreSQL.
Does anyone have recommendations on some settings to use so I can avoid blowing up the server with memory problems due to unnecessary spawning of workers or something like that?
Thanks.

Answer 1

general principles always apply:  use the absolute minimum number of modules.  it's great for security, performance, and simplicity of configuration/maintenance.   Apache comes with a boatload of modules these days, and you really usually need only a few.  The default config should be OK performance wise unless you're really planning on some heavy traffic.
Postgres is another story tho.  There are no modules, but the default config is absolutely minimalistic, it's intended for one local developer and that's it--even the network connectivity is disabled by default!   Postgresql LOVES memory.  the more you give it, the better it's gonna run.  of course if your db is 10mb and you give it 100mb then you wont benefit much from the extra memory, but if it's 10mb and you give it 1mb then you're gonna be running very slowly.  try to fit the whole db in memory if possible.  postgres' memory allocation parameters are _extensive_.  if you like to tweak for performance, you'll go gaga over them.
Generally tho, you won't know what settings you need until you load your data, your site, and you let it run under a normal load for a while.  watch your logs like a hawk and 'learn' your site, how it runs, what gets accessed when, how the db is being used, is the system cpu or io bound, etc...  THEN you can start really adjusting stuff.  Donald Knuth said once that "premature optimization is the root of all evil" and running your own site will definitely demonstrate that.  Log everything, otherwise you'll have nothing to learn from.