Re: mvcc catalo gsnapshots and TopTransactionContext

On 2014-02-05 14:07:29 -0500, Tom Lane wrote:
> I stuck such an Assert in ScanPgRelation, and verified that it doesn't
> break any existing regression tests --- although of course the above
> test case still fails, and now even without declaring an index.
> 
> Barring objections I'll go commit that.  It's a bit pointless to be
> Asserting that catcache.c does nothing unsafe when relcache.c does
> the same things without any such test.
> 
> (Alternatively, maybe we should centralize the asserting in
> systable_beginscan or some such place?)

I don't have a problem with sticking an additional assert elsewhere, but
I think ScanPgRelation, systable_beginscan are a bit late, because they
frequently won't be hit during testing because the lookups will be
cached...

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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