Re: BUG #3245: PANIC: failed to re-find shared loc k ob ject

Dave Page <dpage(at)postgresql(dot)org> writes:
> Heikki Linnakangas wrote:
>> I think we need to see more debug-information. Is there a debug- and
>> assertion-enabled binary available for Windows?

> Unfortunately no - 95% of the time we've found that Mingw/gdb on windows
> simply doesn't work. That's one of the major reasons why we're working
> on moving to VC++.

> I can build one tomorrow if you want to try for the 5%. What version was
> this?

Having assertions turned on would be useful regardless of debug support.
What I was going to suggest was to add some detail printout to the PANIC
message --- in particular, dump the fields of the problem LOCKTAG, so
we can at least find out *what* lock is being lost. If you build a
custom copy for Michel, please add this patch (untested but should work):

*** src/backend/storage/lmgr/lock.c.orig Thu Feb 1 15:09:33 2007
--- src/backend/storage/lmgr/lock.c Sun Apr 22 16:17:01 2007
***************
*** 2430,2437 ****
HASH_FIND,
NULL);
if (!lock)
! elog(PANIC, "failed to re-find shared lock object");
!
/*
* Re-find the proclock object (ditto).
*/
--- 2430,2443 ----
HASH_FIND,
NULL);
if (!lock)
! elog(PANIC, "failed to re-find shared lock object: %u %u %u %u %u %u",
! locktag->locktag_field1,
! locktag->locktag_field2,
! locktag->locktag_field3,
! locktag->locktag_field4,
! locktag->locktag_type,
! locktag->locktag_lockmethodid);
! }
/*
* Re-find the proclock object (ditto).
*/

regards, tom lane