Re: FATAL: lock AccessShareLock on object 0/1260/0 is already held

On Wed, Sep 7, 2011 at 4:55 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Yeah, and for that matter it seems to let VACUUM off the hook too.
> If we assume that the reported object ID is non-corrupt (and if it's
> always the same, that seems like the way to bet) then this is a lock
> on pg_authid.
>
> Hmmm ... could the pathway involve an error exit from client
> authentication?  We're still finding bugs in the 9.0 rewrite of
> auth-time database access.

Well, according to Dave's report upthread, it's not only this one relation:

DG> The recent errors are:
DG> lock AccessShareLock on object 16403/2615/0 is already held
DG> which is for pg_namespace in database c23.

I thought about an error exit from client authentication, and that's a
somewhat appealing explanation, but I can't quite see why we wouldn't
clean up there the same as anywhere else.  The whole mechanism feels a
bit rickety to me - we don't actually release locks; we just abort the
transaction and *assume* that will cause locks to get released.  And
it should.  But there's a bit more action-at-a-distance there than I'd
ideally like.

--
Robert Haas
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