InterBase has an arbitrary limit hardcoded for its data cache at 512MB.
I don't remember if there's any driving reason behind it, it's just a
limit.

I believe it is 512MB _per database_, since Superserver allocates a
separate cache for each database that is currently active on the server.

I think it would be ideal if ibserver set the limit at the maximum
amount of physical RAM on the system (or perhaps leaving some amount for
operating system use). It would be pointless to allocate 1GB of cache
on a system with 128MB of physical RAM.

This assumes that each supported OS has a function to report the amount
of RAM.

Bill

Jason Chapman wrote:

>
> > As I understand it, without adjusting some of the IB parameters, in
> > fact, your 1gb of RAM may not actually being used for the db (or by
> > the OS).
> >
> > I recall reading somewhere that NT uses a maximum of 512Mb for it's
> > file cache. In that case, you would need to specifically configure IB in
> > order to it to "force" the other 512mb to be used for it own purposes.
>
> Why wouldn't it if it is the only significant process running. Moving from
> a 512MB configuration to a 1GB configuration makes a significant improvement
> in performance.