Rename trace_userlocks? WAS Re: LOCK_DEBUG is busted

Robert Haas wrote:
> On Thu, Nov 10, 2011 at 5:07 PM, Bruce Momjian <bruce@momjian.us> wrote:
> > Tom Lane wrote:
> >> Robert Haas <robertmhaas@gmail.com> writes:
> >> > It's possible to compile the source tree with LOCK_DEBUG defined, but
> >> > the resulting postgres promptly dumps core, due to the fact that
> >> > user_lockmethod doesn't supply any value for trace_flag; thus, the
> >> > first LockReleaseAll(USER_LOCKMETHOD) dereferences a NULL pointer.
> >> > This is the result of the following commit:
> >>
> >> > commit 0180bd6180511875db046bf8ddcaa633a2952dfd
> >>
> >> +1 for just reverting that commit. ?I'm not sure how much use the
> >> LOCK_DEBUG infrastructure has in exactly its current form, but I can
> >> certainly imagine wanting to use it or some variant of it to debug
> >> tough problems. ?If it's gone entirely, people would have to reinvent
> >> most of it for that type of debugging. ?On the other side of the coin,
> >> I don't have a clear enough use-case for it to want to spend time
> >> right now on redesigning it, nor a clear idea of exactly what changes
> >> might make it more useful. ?So I think we should just revert and
> >> not spend additional effort now.
> >
> > I am confused. ? I thought it was lock_debug referencing user locks that
> > was broken. ?Does lock_debug need user locks?
> 
> It supports tracing them.
> 
> The point is, they're not gone.

Now that we know that the GUC trace_userlocks is used for advisory
locks, should we rename it to trace_advisory_locks?

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +