| Subject | Re: [firebird-support] Drawbacks of high LockHashSlots value |
|---|---|
| Author | Dmitry Kuzmenko |
| Post date | 2013-09-03T18:51:28Z |
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, www.ib-aid.com
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, www.ib-aid.com