Re: error: could not find pg_class tuple for index 2662

On Fri, Jul 29, 2011 at 11:27 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Fri, Jul 29, 2011 at 9:55 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> The thing that was bizarre about the one instance in the buildfarm was
>>> that the error was persistent, ie, once a session had failed all its
>>> subsequent attempts to access pg_class failed too.
>
>> I was thinking more along the lines of a failure while processing a
>> sinval message emitted by the REINDEX.  The sinval message doesn't get
>> fully processed and therefore we get confused about what the
>> relfilenode is for pg_class.  If that happened for any other relation,
>> we could recover by scanning pg_class.  But if it happens for pg_class
>> or pg_class_oid_index, we're toast, because we can't scan them without
>> knowing what relfilenode to open.
>
> Well, no, because the ScanPgRelation call is not failing internally.
> It's performing a seqscan of pg_class and not finding a matching tuple.

SnapshotNow race?

--
Robert Haas
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