Re: PG 8.3.3 - ERROR: lock AccessShareLock on object 16385/16467/0 is already held

Tom Lane wrote:
> [ reincluding the mailing list ]
>
> Michael Milligan <milli@acmeps.com> writes:
> > Okay, it reproduces and surprise surprise nLocks does overflow...
>
> >  ERROR:  lock AccessShareLock on object 16385/16467/0 is already held
> > lock(0x87408a028) id(16385,16467,0,0,0,1) grantMask(a) waitMask(0)
> > req(2,0,1,0,0,0,0,0)=3 grant(1,0,1,0,0,0,0,0)=2 wait(0)
> > proclock(0x8743a7508) lock(0x87408a028) method(1) proc(0x8743aada8) hold(a)
> > locallock(0xb29c78) nLocks(-2147483648) nOwners(2) mOwners(8)
>
> Hah.  Okay, that shows that we'd never have reproduced it with a small
> test case.

This hasn't been fixed yet, has it?  Do you have any ideas on how to
actually fix the problem?  I wonder if it looks like enlarging nLocks,
or you're intending to attempt to reduce the number of locks taken.

A customer of ours started hitting this bug too, last week.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support