Re: Parallel Append subplan order instability on aye-aye

Andres Freund <andres@anarazel.de> writes:
> On 2019-07-17 11:53:48 -0400, Tom Lane wrote:
>> A brute-force way to fix this (or at least reduce the odds quite a bit)
>> would be to have sanity_check.sql issue a CHECKPOINT before its VACUUM,
>> thereby guaranteeing that none of these pages are still in need of being
>> written.  Not sure how much that'd penalize the regression tests' runtime,
>> or whether we'd have a loss of test coverage of VACUUM behaviors.

> Alternatively we could VACUUM FREEZE the relevant tables? That then
> ought to hit the blocking codepath in lazu_scan_heap()?

If we want to target just the X_star tables, I'd be inclined to do
an ANALYZE instead.  (Although that would create inheritance-tree
statistics, which might change some plan choices?  Haven't tried.)

            regards, tom lane