Sean,

I understand what you are saying.

But, my question is, or should be, more generic.

Something like: "If I have a lot of RAM available, how could I use it in
a way to increase the database speed (specially queries)".

I found out that chaging DefaultDbCachePages from 75 to 750 the queries
really run faster.

Using a ram disk drive increases a query that uses ORDER BY or GROUP BY.

I hope it is a bit more understandable now.

Hugo

Em 20/08/2013 19:22, Leyne, Sean escreveu:

>
> Hugo,
>
> > Hello.
> >
> > I am trying to increase the speed of my queries.
> >
> > Firebird 2.5
> > Windows Server 2008
> > 32 GB RAM
> >
> > I use 10GB of ram as a "ram disk drive".
> >
> > I wrote query that takes 2:45 minutes running _*without*_ the
> > TempDirectories=R:\TEMP (ram disk drive) and the same query takes 1:13
> > minutes running _*with*_ the TempDirectories=R:\TEMP (ram disk drive).
>
> Actually, depending on how you performed your performance testing, it
> may be possible that the RAM disk is having a minimal impact.
>
> If the first query had to load a lot of pages into engine and/or OS
> cache, it would be slower than the second.
>
> > Another question is that using a ram disk drive increases only
> queries that uses
> > ORDER BY or GROUP BY.
>
> Temporarily files can also be used for large query sets.
>
> > How to really increase the speed of my queries using RAM, a lot of RAM?
>
> Without some details regarding the database size, the page cache
> settings, the PLAN for the query and the Statistics for the same, it
> is very difficult to provide meaningful suggestions.
>
> Sean
>
>

--


Atenciosamente,

Hugo Eyng



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