|Subject||Re: Firebird 2.5 performance slower then 2.1 especially SuperClassic...|
> SC (like CS) have very small page cache by default. If your tables have few active indices during INSERT's it will be very slow because of small page cache.I assume you are referring to the DefaultDBCachePages setting?
> Or compare 2.1 CS against 2.5 SC\CS, or set page cache value equal for all tests.
I just had a re-read of the documentation. Not exactly crystal clear. Here it is again:
# This sets the number of pages from any one database that can be held
# in cache at once. If you increase this value, the engine will
# allocate more pages to the cache for every database. By default, the
# SuperServer allocates 2048 pages for each database and the classic
# allocates 75 pages per client connection per database.
Since SuperClassic is a derivative of Classic, then based on above it sounds like SuperClassic is using 75 pages. Someone (Helen?) might want to update this documentation to make it clearer that this applies to SuperClassic.
On a side note... Whomever decided "SuperClassic" was the best name for the SMP based code should be taken out and shot. Far to easy to be confused with the other architecture names and especially deadly for dyslexic people (SC vs CS) and easily susceptible to typos. IMHO I'd have gone with SMP Server or something along those lines. Anyway, just though I'd mention it as I like to stir the pot.
I'll let ya know the results after I've run my test with the bumped up cache.