Thread: Notice Deadlock detected and Backend cache invalidation initialization failed
Notice Deadlock detected and Backend cache invalidation initialization failed
From
Trevor Astrope
Date:
Hello, We're using postgresql 6.4.2 on red hat linux 6.0, kernel 2.2.10 with dbi 1.09 and DBD-Pg 0.91 for web database connectivity. We are occasionally experiencing deadlocks that are logged to the apache logs as follows: NOTICE: Deadlock detected -- See the lock(l) manual page for a possible cause. NOTICE: Deadlock detected -- See the lock(l) manual page for a possible cause. DBD::Pg::st execute failed: ERROR: WaitOnLock: error on wakeup - Aborting this transaction Database handle destroyed without explicit disconnect. Database handle destroyed without explicit disconnect. However, on Friday, we experienced a much more sivere problem where shortly after the Deadlock errors, the following occured: NOTICE: SIAssignBackendId: discarding tag 2147474428 DBI->connect failed: FATAL 1: Backend cache invalidation initialization failed at /home/sitesell/cgi-bin/Database_Interaction//database_func.pl line 727 After this, none of the scripts would execute and generated 500 server errors. When I tried to restart postgresql, I got the following error: Starting postgresql service: IpcMemoryCreate: shmget failed (Identifier removed) key=5432010, size=24588, permission=700 IpcMemoryIdGet: shmget failed (Identifier removed) key=5432010, size=24588, permission=0 IpcMemoryAttach: shmat failed (Invalid argument) id=-2 FATAL 1: AttachSLockMemory: could not attach segment postmaster [] I do have IPC support compiled into the kernel... CONFIG_SYSVIPC=y CONFIG_BSD_PROCESS_ACCT=y CONFIG_SYSCTL=y I don't know if these 2 problems are related or not. If anyone knows the cause for either or both, I'd appreciate any help you could provide. Thanks, Trevor Astrope astrope@e-corp.net
Re: [BUGS] Notice Deadlock detected and Backend cache invalidation initialization failed
From
Bruce Momjian
Date:
> Hello, > > We're using postgresql 6.4.2 on red hat linux 6.0, kernel 2.2.10 with dbi > 1.09 and DBD-Pg 0.91 for web database connectivity. We are occasionally > experiencing deadlocks that are logged to the apache logs as follows: > > NOTICE: Deadlock detected -- See the lock(l) manual page for a possible > cause. > NOTICE: Deadlock detected -- See the lock(l) manual page for a possible > cause. > DBD::Pg::st execute failed: ERROR: WaitOnLock: error on wakeup - Aborting > this transaction > Database handle destroyed without explicit disconnect. > Database handle destroyed without explicit disconnect. > > However, on Friday, we experienced a much more sivere problem where > shortly after the Deadlock errors, the following occured: > > NOTICE: SIAssignBackendId: discarding tag 2147474428 > DBI->connect failed: FATAL 1: Backend cache invalidation initialization > failed > at /home/sitesell/cgi-bin/Database_Interaction//database_func.pl line 727 > > After this, none of the scripts would execute and generated 500 server > errors. When I tried to restart postgresql, I got the following error: > > Starting postgresql service: IpcMemoryCreate: shmget failed (Identifier > removed) key=5432010, size=24588, permission=700 > IpcMemoryIdGet: shmget failed (Identifier removed) key=5432010, > size=24588, permission=0 > IpcMemoryAttach: shmat failed (Invalid argument) id=-2 > FATAL 1: AttachSLockMemory: could not attach segment > postmaster [] My guess is that your shared memory is still allocated to the crashed backends. I recommend using pgsql/bin/ipcclean to clear out your shared memory and restart. As far as the deadlocks, if the lock manual pages doesn't help show the cause, I recommend upgrading to 6.5, where we have new locking code. -- Bruce Momjian | http://www.op.net/~candle maillist@candle.pha.pa.us | (610) 853-3000 + If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania 19026