Show shared object statistics in pg_stat_database

This adds a row to the pg_stat_database view with datoid 0 and datname
NULL for those objects that are not in a database. This was added
particularly for checksums, but we were already tracking more satistics
for these objects, just not returning it.

Also add a checksum_last_failure column that holds the timestamptz of
the last checksum failure that occurred in a database (or in a
non-dataabase file), if any.

Author: Julien Rouhaud <rjuju123@gmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index a68927b57a..fa5dca3b87 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -541,6 +541,7 @@ typedef struct PgStat_MsgChecksumFailure
 	PgStat_MsgHdr m_hdr;
 	Oid			m_databaseid;
 	int			m_failurecount;
+	TimestampTz	m_failure_time;
 } PgStat_MsgChecksumFailure;
 
 
@@ -607,6 +608,7 @@ typedef struct PgStat_StatDBEntry
 	PgStat_Counter n_temp_bytes;
 	PgStat_Counter n_deadlocks;
 	PgStat_Counter n_checksum_failures;
+	TimestampTz last_checksum_failure;
 	PgStat_Counter n_block_read_time;	/* times in microseconds */
 	PgStat_Counter n_block_write_time;