Hi,
we're running Firebird 2.5.7 SuperClassic on Windows Server 2012R2 as part of a
web application. Database is around 130GB with millions of transaction per day.
From time to time Firebird hangs. It does not respond to any client. It's also
not possible to connect locally to the server. The interesting thing is the
memory consumption that drops from 5-7GB to around 50MB and the CPU load goes
down to 0%. When Firebird is in this state, I also see a lot of waiting threads
in the Task Manager under "Analyze wait chain". The only way to get out, is to
stop the service. This takes longer than normal and sometimes shows some kind
of timeout. But the process is stopped and can be started again. I also ran
fb_lock_print when the problem occurred. It shows something under "Deadlock
scans" which is not normal, I think.
LOCK_HEADER BLOCK
Version: 145, Active owner: 0, Length: 25165824, Used:
24798216
Flags: 0x0001
Enqs: 17157097538, Converts: 22693011, Rejects: 12135777,
Blocks: 93039760
Deadlock scans: 289, Deadlocks: 1, Scan interval: 10
Acquires: 18346589405, Acquire blocks: 1203176111, Spin count:
0
Mutex wait: 6.6%
Hash slots: 1009, Hash lengths (min/avg/max): 47/ 67/ 93
Remove node: 0, Insert queue: 0, Insert prior: 0
Owners (151): forward: 30704, backward: 21097392
Free owners (4): forward: 750216, backward: 24346456
Free locks (10120): forward: 28728, backward: 693760
Free requests (7877): forward: 8570432, backward: 1678000
Lock Ordering: Enabled
Has anybody experienced something like this? Thanks in advance.
Best regards
Freddy Ertl
