diff options
| author | Amit Kapila | 2021-04-27 03:39:11 +0000 |
|---|---|---|
| committer | Amit Kapila | 2021-04-27 03:39:11 +0000 |
| commit | 3fa17d37716f978f80dfcdab4e7c73f3a24e7a48 (patch) | |
| tree | 43a865e413ebd2852e418535b8fbbdb4a83d6d78 /src/test | |
| parent | e7eea52b2d61917fbbdac7f3f895e4ef636e935b (diff) | |
Use HTAB for replication slot statistics.
Previously, we used to use the array of size max_replication_slots to
store stats for replication slots. But that had two problems in the cases
where a message for dropping a slot gets lost: 1) the stats for the new
slot are not recorded if the array is full and 2) writing beyond the end
of the array if the user reduces the max_replication_slots.
This commit uses HTAB for replication slot statistics, resolving both
problems. Now, pgstat_vacuum_stat() search for all the dead replication
slots in stats hashtable and tell the collector to remove them. To avoid
showing the stats for the already-dropped slots, pg_stat_replication_slots
view searches slot stats by the slot name taken from pg_replication_slots.
Also, we send a message for creating a slot at slot creation, initializing
the stats. This reduces the possibility that the stats are accumulated
into the old slot stats when a message for dropping a slot gets lost.
Reported-by: Andres Freund
Author: Sawada Masahiko, test case by Vignesh C
Reviewed-by: Amit Kapila, Vignesh C, Dilip Kumar
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/regress/expected/rules.out | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out index 6dff5439e00..572bc2057cc 100644 --- a/src/test/regress/expected/rules.out +++ b/src/test/regress/expected/rules.out @@ -2071,7 +2071,9 @@ pg_stat_replication_slots| SELECT s.slot_name, s.total_txns, s.total_bytes, s.stats_reset - FROM pg_stat_get_replication_slots() s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset); + FROM pg_replication_slots r, + LATERAL pg_stat_get_replication_slot((r.slot_name)::text) s(slot_name, spill_txns, spill_count, spill_bytes, stream_txns, stream_count, stream_bytes, total_txns, total_bytes, stats_reset) + WHERE (r.datoid IS NOT NULL); pg_stat_slru| SELECT s.name, s.blks_zeroed, s.blks_hit, |