It appears that a concurrent autovacuum/autoanalyze run can cause
changes in the plans expected by this test. To prevent that, change
the tables it uses to be temp tables --- there's no need for them
to be permanent, and this should save a few cycles too.
Discussion: https://postgr.es/m/3244.1576160824@sss.pgh.pa.us
At least buildfarm member florican doesn't use a material node above a
sort in the mark/restore case. As material is not intended to be
tested with that query, disallow.
Previously significant parts of tuplesort.c were untested. This
commit, while not testing every path, significantly increases
coverage. In particular, this adds tests for abbreviated key logic,
forward/backward scans & scrolling and mark/restore.
I tried to keep the table sizes reasonable, and stress the on-disk
paths by setting work_mem to low values for specific tests. The
buildfarm will tell whether more attention to test time is needed.
Author: Andres Freund
Discussion: https://postgr.es/m/20191013144153.ooxrfglvnaocsrx2@alap3.anarazel.de
Amit Kapila
Michael Paquier
Tom Lane
Andres Freund