index 937b2101b33cc8728ff1c7f93532ffdf6ea360c5..186c2962990f7d234a2992830dd1f1650794eee1 100644 (file)
-- from it to cause it to be read back into shared buffers.
SELECT sum(reads) AS io_sum_shared_before_reads
FROM pg_stat_io WHERE io_context = 'normal' AND io_object = 'relation' \gset
+-- Do this in a transaction to prevent spurious failures due to concurrent accesses to our newly
+-- rewritten table, e.g. by autovacuum.
+BEGIN;
ALTER TABLE test_io_shared SET TABLESPACE regress_tblspace;
-- SELECT from the table so that the data is read into shared buffers and
-- io_context 'normal', io_object 'relation' reads are counted.
100
(1 row)
+COMMIT;
SELECT pg_stat_force_next_flush();
pg_stat_force_next_flush
--------------------------
index 74e592aa8af8e72fe1c04cfd01aa6e50ebf76447..d7f873cfc9d89d20a0e7d8227ecdbbf6c8fa6f6f 100644 (file)
-- from it to cause it to be read back into shared buffers.
SELECT sum(reads) AS io_sum_shared_before_reads
FROM pg_stat_io WHERE io_context = 'normal' AND io_object = 'relation' \gset
+-- Do this in a transaction to prevent spurious failures due to concurrent accesses to our newly
+-- rewritten table, e.g. by autovacuum.
+BEGIN;
ALTER TABLE test_io_shared SET TABLESPACE regress_tblspace;
-- SELECT from the table so that the data is read into shared buffers and
-- io_context 'normal', io_object 'relation' reads are counted.
SELECT COUNT(*) FROM test_io_shared;
+COMMIT;
SELECT pg_stat_force_next_flush();
SELECT sum(reads) AS io_sum_shared_after_reads
FROM pg_stat_io WHERE io_context = 'normal' AND io_object = 'relation' \gset