> Stuart,
>
> > I'm putting together a road map on how our systems can scale as our
load
> > increases. As part of this, I need to look into setting up some fast
> > read only mirrors of our database. We should have more than enough
RAM
> > to fit everything into memory. I would like to find out if I could
> > expect better performance by mounting the database from a RAM disk,
or
> > if I would be better off keeping that RAM free and increasing the
> > effective_cache_size appropriately.
>
> If you're accessing a dedicated, read-only system with a database
small
> enough to fit in RAM, it'll all be cached there anyway, at least on
Linux
> and BSD. You won't be gaining anything by creating a ramdisk.
ditto windows.
Files cached in memory are slower than reading straight from memory but
not nearly enough to justify reserving memory for your use. In other
words, your O/S is a machine with years and years of engineering
designed best how to dole memory out to caching and various processes.
Why second guess it?
Merlin