Re: Writing WAL for relcache invalidation:pg_internal.init

"Simon Riggs" <simon@2ndquadrant.com> writes:
> On Wed, 2006-11-01 at 12:05 -0500, Tom Lane wrote:
>> I don't think this works.

> Surely you are pointing out a bug, no?

> If a backend did crash, the init file would be wrong and we'd get
> exactly the same wrong relfilenode errors we got after that PITR.

Yeah, which is the same bug we've got now.  They're both WAL-replay-
doesn't-fix-the-init-file cases.

> The issue must surely be that the patch isn't wrong per se, just that
> RelationCacheInitFileInvalidate is called too late and that requires an
> additional fix.

No.  In the non-crash situation there is sufficient interlocking to
avoid a problem, and I feel no desire to redesign that mechanism.
Trying to do it before commit would create its own issues, anyway:
someone could install a new init file before you finish committing.

            regards, tom lane