Re: pgsql: Test decoding of two-phase transactions during the build of a co

Amit Kapila <akapila@postgresql.org> writes:
> Test decoding of two-phase transactions during the build of a consistent snapshot.

It seems this test case isn't 100% stable:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=chipmunk&dt=2021-01-08%2023%3A56%3A57

========================== output_iso/regression.diffs ================
diff -U3 /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/expected/twophase_snapshot.out
/home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/output_iso/results/twophase_snapshot.out
--- /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/expected/twophase_snapshot.out    2021-01-07
02:49:30.231809843+0200 
+++ /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/output_iso/results/twophase_snapshot.out
2021-01-0904:01:26.730510078 +0200 
@@ -26,6 +26,8 @@
 data

 BEGIN
+COMMIT
+BEGIN
 table public.do_write: INSERT: id[integer]:2
 COMMIT
 step s2cp: COMMIT PREPARED 'test1';
@@ -33,6 +35,10 @@
 data

 BEGIN
+COMMIT
+BEGIN
+COMMIT
+BEGIN
 table public.do_write: INSERT: id[integer]:1
 PREPARE TRANSACTION 'test1'
 COMMIT PREPARED 'test1'

I think we've seen this extra-transactions symptom before,
but I don't recall the details at this late hour.

            regards, tom lane