Re: FailedAssertion("!(PrivateRefCount[i] == 0)", File: "bufmgr.c", Line: 1741

On Wed, May 30, 2012 at 2:52 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Wed, May 30, 2012 at 1:47 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>>> The process holding the AccessExclusiveLock is the startup process. It's
>>> holding the lock on behalf of the transaction in the master. But something's
>>> wrong, and the AccessExclusiveLock doesn't stop a regular backend from
>>> acquiring the AccessShareLock on the table. I suspect the fast-path locking
>>> patch, because this works on 9.1.
>>
>> Yeah, apparently so.  gdb says that FastPathStrongRelationLocks on the
>> standby is all-zeros even after that record has been replayed.  Not
>> sure how that's possible yet.
>
> Ah.  The problem is that FastPathTag() expects that locks on database
> objects will only be taken by backends with a non-zero value for
> MyDatabaseId.  Apparently the can-i-use-the-fastpath test and the
> do-i-need-to-force-other-people-out-of-the-fastpath test need to be a
> bit more asymmetrical than they are at present.

I've fixed things so that Heikki's test case now behaves as expected.
Hopefully this fixes Erik's problem as well, but I haven't tested.

--
Robert Haas
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