Subject | Firebird's default settings |
---|---|
Author | Josef Kokeš |
Post date | 2012-07-16T08:46:50Z |
Hi!
I have never tried to change Firebird's default settings, because the
server has always been "good enough" and "if it isn't broken, don't fix
it". But I can't help but wonder about some of the settings, because I
don't understand their default values. Specifically, assuming Firebird
2.5 in the default install (which, I believe, is using SuperServer):
- CpuAffinityMask - I can see why the value 1 would be a safe lower
bound, but why doesn't the server default to a value which would use all
available CPU cores? (That is, if CpuAffinityMask is not explicitly set,
use all available CPUs.) Can I expect some adverse effects from setting
CpuAffinityMask to 3 on a dual core system?
- DefaultDbCachePages - why the value 2048? Given the usual settings,
that means only 8 MB is used for database cache (per database). Today's
computers tend to have 2 or more GB RAM, wouldn't it make more sense to
default to 65536 or even 262144 pages? Again, if I increase the number
to say 131072 pages (8192 bytes page size, one database only) on a 2.5
GB RAM system, can I expect any adverse effects?
Thanks,
Pepak
I have never tried to change Firebird's default settings, because the
server has always been "good enough" and "if it isn't broken, don't fix
it". But I can't help but wonder about some of the settings, because I
don't understand their default values. Specifically, assuming Firebird
2.5 in the default install (which, I believe, is using SuperServer):
- CpuAffinityMask - I can see why the value 1 would be a safe lower
bound, but why doesn't the server default to a value which would use all
available CPU cores? (That is, if CpuAffinityMask is not explicitly set,
use all available CPUs.) Can I expect some adverse effects from setting
CpuAffinityMask to 3 on a dual core system?
- DefaultDbCachePages - why the value 2048? Given the usual settings,
that means only 8 MB is used for database cache (per database). Today's
computers tend to have 2 or more GB RAM, wouldn't it make more sense to
default to 65536 or even 262144 pages? Again, if I increase the number
to say 131072 pages (8192 bytes page size, one database only) on a 2.5
GB RAM system, can I expect any adverse effects?
Thanks,
Pepak