Subject RE: [firebird-support] RE: Firebird SuperClassic hangs
Author Freddy Ertl
With "hang" I really mean stop working, not just slow. There is absolutely nothing in the log file that indicates an error. It just does not respond anymore. I also waited a couple of minutes to see if it recovers, but it does not.

Am 04.05.2017 11:21 nachm. schrieb "'Leyne, Sean' Sean@... [firebird-support]" <>:


Thank you for your suggestion. I know that our configuration is not optimal and I will change this. But my understanding was, that this is only a performance problem and not something that can cause Firebird to hang. Or is this a known behavior?


<SL> The problem is in the definition of “hang”.


<SL> Does Firebird hang, ie. plain stop?  No


<SL> Can the deadlock scans and lock contention (see Mutex Wait) make Firebird appear to be hung/running really slow?  Yes



<SL> FYI, we are considering changing from Classic to SuperClassic to eliminate the overhead (10-15%) that the external lock manager adds.  Like you, our databases can be very large (300GB) and have a large number of connection (sometimes 800).  This may be something that you also evaluate.