Re: hung backends stuck in spinlock heavy endless loop

On 2015-01-15 20:15:42 +0100, Andres Freund wrote:
> > WARNING: did not find subXID 14955 in MyProc
> > CONTEXT: PL/pgSQL function cdsreconcileruntable(bigint) line 35
> > during exception cleanup
> > WARNING: you don't own a lock of type RowExclusiveLock
> > CONTEXT: PL/pgSQL function cdsreconcileruntable(bigint) line 35
> > during exception cleanup
> > LOG: could not send data to client: Broken pipe
> > CONTEXT: PL/pgSQL function cdsreconcileruntable(bigint) line 35
> > during exception cleanup
> > STATEMENT: SELECT CDSReconcileRunTable(2151)
> > WARNING: ReleaseLockIfHeld: failed??
> > CONTEXT: PL/pgSQL function cdsreconcileruntable(bigint) line 35
> > during exception cleanup
> > ERROR: failed to re-find shared proclock object
> > CONTEXT: PL/pgSQL function cdsreconcileruntable(bigint) line 35
> > during exception cleanup
> > STATEMENT: SELECT CDSReconcileRunTable(2151)
> > WARNING: AbortSubTransaction while in ABORT state
> > WARNING: did not find subXID 14955 in MyProc
> > WARNING: you don't own a lock of type AccessShareLock
> > WARNING: ReleaseLockIfHeld: failed??
> > ERROR: failed to re-find shared proclock object
> > WARNING: AbortSubTransaction while in ABORT state
> > WARNING: did not find subXID 14955 in MyProc
> > WARNING: you don't own a lock of type AccessShareLock
> > WARNING: ReleaseLockIfHeld: failed??
> > WARNING: you don't own a lock of type ShareLock
> > TRAP: FailedAssertion("!(FastPathStrongRelationLocks->count[fasthashcode]
> > > 0)", File: "lock.c", Line: 1240)
> > LOG: server process (PID 10117) was terminated by signal 6: Aborted
> > LOG: terminating any other active server processes
>
> Ick.
>
> Were there any 'LOG: Handling deadlock detected on CdsRunTableId' log
> entries before? It's hard to know from here, but the 'during exception
> cleanup' indicates a problem in abort handling. Were there any deadlock
> detected errors closeby?

Alternatively were there any 'LOG: CdsRunTableId %s Failed' messages? If
so, what was the cause?

> You're catching deadlock errors in a subtransaction. Hm.

A couple questions:
* Do you also use lock_timeout/statement_timeout? If so, what are their
settings + deadlock_timeout?
* were any processes killed at that time?

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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