Subject Re: [firebird-support] Effect of DefaultDbCachePages?
Author Gabor Boros
Ivan Prenosil írta:
> When you connect to the database and no connection is established yet,
> FB server will allocate cache memory. The size of cache is determined that way:
> 1) if the database has specified cache size (e.g. using gfix), then that value is used. Period.
> otherwise

Database cache size specified every time. When create a new database the
cache size come from DefaultDbCachePages. I tried now gfix.exe OPHHA
-buffers 0 and the cache size set to DefaultDbCachePages. If cache size
now 2049 and try set to 0 with gfix the new value in database is 2048.
The name of the option (DefaultDbCachePages) is godd for me. This is the
default cache size in newly created databases. But the description in
firebird.conf say diferrent things or I have problems with English. ;-)

> 2) if you specified cache size during connection, that value is used,
> otherwise
> 3) DefaultDbCachePages is used.
> When the application connects to the database using isc_attach_database() FB API call,
> it can specify desired cache size by isc_dpb_num_buffers value. If you do not use FB API directly,
> you have to consult documentation of your connect library or application.
> E.g. with ISQL you can specify that value as command line parameter "-cache 12345",
> or in FSQL tool you can specify that value as part of Connect command like
> CONNECT 'MyDatabase' USER 'TEST' PASSWORD 'test' CACHE 12345;
> etc.
> Ivan