Dror Matalon wrote:
> Let me try and say it again. I know that setting effective_cache_size
> doesn't affect the OS' cache. I know it just gives Postgres the *idea*
> of how much cache the OS is using. I know that. I also know that a
> correct hint helps performance.
>
> I've read Matt Dillon's discussion about the freebsd VM at
> http://www.daemonnews.org/200001/freebsd_vm.html and I didn't see him
> saying that Freebsd uses all the free RAM for disk cache. Would you care
> to provide a URL pointing to that?
I don't believe freeBSD yses everything available unlike linux. It is actually a
good thing. If you have 1GB RAM and kernel buffers set at 600MB, you are
guaranteed to have some mmory in crunch situations.
As far you original questions, I think you can increase the kernel buffer sizes
for VFS safely. However remembet that more to dedicate to kernel buffers, less
space you have in case of crunch for whatever reasons.
FreeBSD gives you a control which linux does not. Use it to best of your advantage..
Shridhar
