> --- In firebird-support@yahoogroups.com, "Alan McDonald" <alan@m...>
> wrote:
> > > I know 14MB doesn't sound like much, but we're installing this on a
> > > wide range of hardware, and we're also looking for small footprint and
> > > speed, so this is important to us.
> > >
> > > Thanks
> > > Phil
> >
> > the default page size has changed - you can manually set the page
> size back
> > but a larger page size than the earlier 1024 has always been beter
> for most
> > cases.
> > create a new empty database in both environments by specifying page
> size and
> > you should get the same empty database
> > Alan
>
> Thanks Alan, this is good to know. This may also explain the
> difference in speed - we pull in 80MB of data in a migration (300-400k
> records), which used to take 50+ minutes and is now only 30 minutes
> (however some queries seem longer ... maybe).
>
> Anyway, I've been looking on the ibphoenix site for docs on
> strategy/methodology for choosing the optimal paging size. I couldn't
> find one (maybe I missed one) - do you know of any docs/links covering
> this?
>
> Thanks again
> Phil

AFAIK there is no real science to it. It very much depends on how many
blob/large varchar fields you have in a table and what sort of queries you
expect to use. If you can get all your queries coming from a single page at
any one time then that's great. If you have smallish tables and they all
have smallint fields, then I would go for a small page size. but as soon as
you start using varchars and blobs, it's best to go larger. Also remember
that going too large can reduce performance as well. I think most people
accept that 4096 is a good default. You can try 8192 but using 16384 might
not behave as well as you expect. It's trial and error I'm afraid.
Alan