Subject Re: [firebird-support] Help, tunning database
Author Mark Rotteveel
On 15-7-2013 16:31, trskopo wrote:
> Hi all,
> I have Superserver Firebird 2.5.1 installed on Win7 pro 64 bit on I7 2600K.
> When data grows, Firebird Server starting to slow down. I shutdown Firebird Server, starting again without changing anything and Firebird Server became smooth again.
> Any ideas, what is the problem with this? Firebird.conf mostly on its default values except for cpuaffinity set to 15 and DefaultDbCachePages set to 4096.

Setting CpuAffinity to anything other than 2^n is a bad idea as it can
cause slow down because of migrating threads to other cores.

DefaultDbCachePages controls the number of pages in cache per database
(if no specific value is configured for the database itself).

With 4k pages, the value of 4096 means a page cache of only 16MB.
With 16k pages: 64MB

You might want to consider increasing it a bit more, or switching to
classic or superclassic server.

As you use Windows 7 64, you might actually be bitten by the filesystem
cache issue, where Windows tries to cache beyond the available physical
memory. See
for settings to control this (although I believe you shouldn't be
affected with the default setting).

Mark Rotteveel