Subject Re: [firebird-support] Drawbacks of high LockHashSlots value
Author Dmitry Kuzmenko
Hello, Fabiano!

Tuesday, September 3, 2013, 9:38:47 PM, you wrote:

FDS> Mutex wait: 37.6%
FDS> Hash slots: 1009, Hash lengths (min/avg/max): 74/ 98/ 128
FDS> Terrible numbers. Then I disconnect everything, chang LockHashSlots in
FDS> Firebird.conf to 4093 (more or less 4 times more that default 1009 and still
FDS> a prime number) and now the HDD is running smoth!

Yes, we have several cases at different production environments with
high load (Windows, Linux), and found that high LockHashSlots value helps a lot.

The good value is around 10000.

BTW, Firebird 1.5 ignores value higher than 2048, IIRC.
Other Firebird versions accepts higher values without problems.

Dmitry Kuzmenko,