Re: [HACKERS] Postgres Performance

Edwin Ramirez <ramirez@doc.mssm.edu> writes:
> I have a couple of large(?) tables which I would like to keep them in
> memory (cached) so that searches are performed as fast as possible.
> Is it possible to 'pin' the tables and it's indexes in memory?  

If the tables are being touched often, then they will stay in buffer
cache of their own accord.  I doubt that pinning them would improve
performance --- if they do get swapped out it'd be because some other
table(s) need to be accessed now, and if you did have these tables
pinned you'd be taking a large hit in access performance for those other
tables because of inadequate buffer space.  LRU buffering policy really
works pretty well, so I don't think you need to worry about it.

> currently I run the postmaster with the following setting: 
>     postmaster -i -B 2048 -o '-S 2048'
> Are there any other options/values which would yield better performance?

If you have a reliable OS and power source, consider -o -F (no fsync).
This usually makes for a very substantial performance improvement, and
it can only hurt if your machine goes down without having performed
all the writes the kernel was told to do.
        regards, tom lane