pg-stat-statements-planning-v2.patch

From 56d2884a9d958fc52ad512c39f9c3fed52abb356 Mon Sep 17 00:00:00 2001
From: Thomas Munro <thomas.munro@enterprisedb.com>
Date: Tue, 7 Nov 2017 17:33:24 +1300
Subject: [PATCH] Add plan count and time to pg_stat_statements.

This allows administrators to look out for statements that should ideally be
changed to prepared statements, and monitor how often prepared statements
are [re]planned.

Author: Fujii Masao and Thomas Munro
Reviewed-By: Haribabu Kommi
Discussion: https://postgr.es/m/CAEepm%3D0e59Y_6Q_YXYCTHZkqOc6H2pJ54C_Xe%3DVFu50Aqqp_sA%40mail.gmail.com
Discussion: https://postgr.es/m/CAHGQGwFx_%3DDO-Gu-MfPW3VQ4qC7TfVdH2zHmvZfrGv6fQ3D-Tw%40mail.gmail.com
---
 contrib/pg_stat_statements/Makefile                |   3 +-
 .../expected/pg_stat_statements.out                |  64 ++++++++++++
 .../pg_stat_statements--1.5--1.6.sql               |  49 +++++++++
 ...ements--1.4.sql => pg_stat_statements--1.6.sql} |   8 +-
 contrib/pg_stat_statements/pg_stat_statements.c    | 110 +++++++++++++++++++--
 .../pg_stat_statements/pg_stat_statements.control  |   2 +-
 .../pg_stat_statements/sql/pg_stat_statements.sql  |  16 +++
 doc/src/sgml/pgstatstatements.sgml                 |  27 +++--
 src/backend/nodes/copyfuncs.c                      |   1 +
 src/backend/nodes/outfuncs.c                       |   1 +
 src/backend/nodes/readfuncs.c                      |   1 +
 src/backend/optimizer/plan/planner.c               |   1 +
 src/include/nodes/plannodes.h                      |   3 +
 13 files changed, 269 insertions(+), 17 deletions(-)
 create mode 100644 contrib/pg_stat_statements/pg_stat_statements--1.5--1.6.sql
 rename contrib/pg_stat_statements/{pg_stat_statements--1.4.sql => pg_stat_statements--1.6.sql} (84%)

diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index 39b368b70eb..d21e9a83a32 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -4,7 +4,8 @@ MODULE_big = pg_stat_statements
 OBJS = pg_stat_statements.o $(WIN32RES)
 
 EXTENSION = pg_stat_statements
-DATA = pg_stat_statements--1.4.sql pg_stat_statements--1.4--1.5.sql \
+DATA = pg_stat_statements--1.6.sql \
+	pg_stat_statements--1.5--1.6.sql pg_stat_statements--1.4--1.5.sql \
 	pg_stat_statements--1.3--1.4.sql pg_stat_statements--1.2--1.3.sql \
 	pg_stat_statements--1.1--1.2.sql pg_stat_statements--1.0--1.1.sql \
 	pg_stat_statements--unpackaged--1.0.sql
diff --git a/contrib/pg_stat_statements/expected/pg_stat_statements.out b/contrib/pg_stat_statements/expected/pg_stat_statements.out
index 5318c3550c7..76669176447 100644
--- a/contrib/pg_stat_statements/expected/pg_stat_statements.out
+++ b/contrib/pg_stat_statements/expected/pg_stat_statements.out
@@ -395,4 +395,68 @@ SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
  SELECT pg_stat_statements_reset()         |     1 |    1
 (8 rows)
 
+--
+-- [re]plan counting
+--
+SELECT pg_stat_statements_reset();
+ pg_stat_statements_reset 
+--------------------------
+ 
+(1 row)
+
+CREATE TABLE test ();
+PREPARE prep1 AS SELECT COUNT(*) FROM test;;
+EXECUTE prep1;
+ count 
+-------
+     0
+(1 row)
+
+EXECUTE prep1;
+ count 
+-------
+     0
+(1 row)
+
+EXECUTE prep1;
+ count 
+-------
+     0
+(1 row)
+
+ALTER TABLE test ADD COLUMN x int;
+EXECUTE prep1;
+ count 
+-------
+     0
+(1 row)
+
+SELECT 42;
+ ?column? 
+----------
+       42
+(1 row)
+
+SELECT 42;
+ ?column? 
+----------
+       42
+(1 row)
+
+SELECT 42;
+ ?column? 
+----------
+       42
+(1 row)
+
+SELECT query, plans, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
+                   query                    | plans | calls | rows 
+--------------------------------------------+-------+-------+------
+ ALTER TABLE test ADD COLUMN x int          |     0 |     1 |    0
+ CREATE TABLE test ()                       |     0 |     1 |    0
+ PREPARE prep1 AS SELECT COUNT(*) FROM test |     2 |     4 |    4
+ SELECT $1                                  |     3 |     3 |    3
+ SELECT pg_stat_statements_reset()          |     1 |     1 |    1
+(5 rows)
+
 DROP EXTENSION pg_stat_statements;
diff --git a/contrib/pg_stat_statements/pg_stat_statements--1.5--1.6.sql b/contrib/pg_stat_statements/pg_stat_statements--1.5--1.6.sql
new file mode 100644
index 00000000000..3cb6eec081e
--- /dev/null
+++ b/contrib/pg_stat_statements/pg_stat_statements--1.5--1.6.sql
@@ -0,0 +1,49 @@
+/* contrib/pg_stat_statements/pg_stat_statements--1.5--1.6.sql */
+
+-- complain if script is sourced in psql, rather than via ALTER EXTENSION
+\echo Use "ALTER EXTENSION pg_stat_statements UPDATE TO '1.6'" to load this file. \quit
+
+/* First we have to remove them from the extension */
+ALTER EXTENSION pg_stat_statements DROP VIEW pg_stat_statements;
+ALTER EXTENSION pg_stat_statements DROP FUNCTION pg_stat_statements(boolean);
+
+/* Then we can drop them */
+DROP VIEW pg_stat_statements;
+DROP FUNCTION pg_stat_statements(boolean);
+
+/* Now redefine */
+CREATE FUNCTION pg_stat_statements(IN showtext boolean,
+    OUT userid oid,
+    OUT dbid oid,
+    OUT queryid bigint,
+    OUT query text,
+    OUT plans int8,
+    OUT planning_time float8,
+    OUT calls int8,
+    OUT total_time float8,
+    OUT min_time float8,
+    OUT max_time float8,
+    OUT mean_time float8,
+    OUT stddev_time float8,
+    OUT rows int8,
+    OUT shared_blks_hit int8,
+    OUT shared_blks_read int8,
+    OUT shared_blks_dirtied int8,
+    OUT shared_blks_written int8,
+    OUT local_blks_hit int8,
+    OUT local_blks_read int8,
+    OUT local_blks_dirtied int8,
+    OUT local_blks_written int8,
+    OUT temp_blks_read int8,
+    OUT temp_blks_written int8,
+    OUT blk_read_time float8,
+    OUT blk_write_time float8
+)
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'pg_stat_statements_1_4'
+LANGUAGE C STRICT VOLATILE PARALLEL SAFE;
+
+CREATE VIEW pg_stat_statements AS
+  SELECT * FROM pg_stat_statements(true);
+
+GRANT SELECT ON pg_stat_statements TO PUBLIC;
diff --git a/contrib/pg_stat_statements/pg_stat_statements--1.4.sql b/contrib/pg_stat_statements/pg_stat_statements--1.6.sql
similarity index 84%
rename from contrib/pg_stat_statements/pg_stat_statements--1.4.sql
rename to contrib/pg_stat_statements/pg_stat_statements--1.6.sql
index 58cdf600fce..0ddd6162eb0 100644
--- a/contrib/pg_stat_statements/pg_stat_statements--1.4.sql
+++ b/contrib/pg_stat_statements/pg_stat_statements--1.6.sql
@@ -1,4 +1,4 @@
-/* contrib/pg_stat_statements/pg_stat_statements--1.4.sql */
+/* contrib/pg_stat_statements/pg_stat_statements--1.6.sql */
 
 -- complain if script is sourced in psql, rather than via CREATE EXTENSION
 \echo Use "CREATE EXTENSION pg_stat_statements" to load this file. \quit
@@ -14,6 +14,8 @@ CREATE FUNCTION pg_stat_statements(IN showtext boolean,
     OUT dbid oid,
     OUT queryid bigint,
     OUT query text,
+    OUT plans int8,
+    OUT planning_time float8,
     OUT calls int8,
     OUT total_time float8,
     OUT min_time float8,
@@ -35,7 +37,7 @@ CREATE FUNCTION pg_stat_statements(IN showtext boolean,
     OUT blk_write_time float8
 )
 RETURNS SETOF record
-AS 'MODULE_PATHNAME', 'pg_stat_statements_1_3'
+AS 'MODULE_PATHNAME', 'pg_stat_statements_1_4'
 LANGUAGE C STRICT VOLATILE PARALLEL SAFE;
 
 -- Register a view on the function for ease of use.
@@ -46,3 +48,5 @@ GRANT SELECT ON pg_stat_statements TO PUBLIC;
 
 -- Don't want this to be available to non-superusers.
 REVOKE ALL ON FUNCTION pg_stat_statements_reset() FROM PUBLIC;
+
+GRANT EXECUTE ON FUNCTION pg_stat_statements_reset() TO pg_read_all_stats;
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index 928673498af..1bec296f58e 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -1,7 +1,7 @@
 /*-------------------------------------------------------------------------
  *
  * pg_stat_statements.c
- *		Track statement execution times across a whole database cluster.
+ *		Track statement planning and execution times across a whole cluster.
  *
  * Execution costs are totalled for each distinct source query, and kept in
  * a shared hashtable.  (We track only as many distinct queries as will fit
@@ -67,6 +67,7 @@
 #include "funcapi.h"
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
+#include "optimizer/planner.h"
 #include "parser/analyze.h"
 #include "parser/parsetree.h"
 #include "parser/scanner.h"
@@ -119,7 +120,8 @@ typedef enum pgssVersion
 	PGSS_V1_0 = 0,
 	PGSS_V1_1,
 	PGSS_V1_2,
-	PGSS_V1_3
+	PGSS_V1_3,
+	PGSS_V1_4
 } pgssVersion;
 
 /*
@@ -149,6 +151,8 @@ typedef struct Counters
 	double		max_time;		/* maximum execution time in msec */
 	double		mean_time;		/* mean execution time in msec */
 	double		sum_var_time;	/* sum of variances in execution time in msec */
+	int64		plans;			/* # of times planned */
+	double		planning_time;	/* total planning time, in msec */
 	int64		rows;			/* total # of retrieved or affected rows */
 	int64		shared_blks_hit;	/* # of shared buffer hits */
 	int64		shared_blks_read;	/* # of shared disk blocks read */
@@ -237,6 +241,7 @@ static int	nested_level = 0;
 
 /* Saved hook values in case of unload */
 static shmem_startup_hook_type prev_shmem_startup_hook = NULL;
+static planner_hook_type prev_planner_hook = NULL;
 static post_parse_analyze_hook_type prev_post_parse_analyze_hook = NULL;
 static ExecutorStart_hook_type prev_ExecutorStart = NULL;
 static ExecutorRun_hook_type prev_ExecutorRun = NULL;
@@ -291,10 +296,14 @@ void		_PG_fini(void);
 PG_FUNCTION_INFO_V1(pg_stat_statements_reset);
 PG_FUNCTION_INFO_V1(pg_stat_statements_1_2);
 PG_FUNCTION_INFO_V1(pg_stat_statements_1_3);
+PG_FUNCTION_INFO_V1(pg_stat_statements_1_4);
 PG_FUNCTION_INFO_V1(pg_stat_statements);
 
 static void pgss_shmem_startup(void);
 static void pgss_shmem_shutdown(int code, Datum arg);
+static PlannedStmt *pgss_planner_hook(Query *parse,
+									  int cursorOptions,
+									  ParamListInfo boundParams);
 static void pgss_post_parse_analyze(ParseState *pstate, Query *query);
 static void pgss_ExecutorStart(QueryDesc *queryDesc, int eflags);
 static void pgss_ExecutorRun(QueryDesc *queryDesc,
@@ -309,7 +318,9 @@ static void pgss_ProcessUtility(PlannedStmt *pstmt, const char *queryString,
 static uint64 pgss_hash_string(const char *str, int len);
 static void pgss_store(const char *query, uint64 queryId,
 		   int query_location, int query_len,
-		   double total_time, uint64 rows,
+		   double total_time,
+		   double planning_time,
+		   uint64 rows,
 		   const BufferUsage *bufusage,
 		   pgssJumbleState *jstate);
 static void pg_stat_statements_internal(FunctionCallInfo fcinfo,
@@ -422,6 +433,8 @@ _PG_init(void)
 	 */
 	prev_shmem_startup_hook = shmem_startup_hook;
 	shmem_startup_hook = pgss_shmem_startup;
+	prev_planner_hook = planner_hook;
+	planner_hook = pgss_planner_hook;
 	prev_post_parse_analyze_hook = post_parse_analyze_hook;
 	post_parse_analyze_hook = pgss_post_parse_analyze;
 	prev_ExecutorStart = ExecutorStart_hook;
@@ -445,6 +458,7 @@ _PG_fini(void)
 	/* Uninstall hooks. */
 	shmem_startup_hook = prev_shmem_startup_hook;
 	post_parse_analyze_hook = prev_post_parse_analyze_hook;
+	planner_hook = prev_planner_hook;
 	ExecutorStart_hook = prev_ExecutorStart;
 	ExecutorRun_hook = prev_ExecutorRun;
 	ExecutorFinish_hook = prev_ExecutorFinish;
@@ -770,6 +784,54 @@ error:
 	unlink(PGSS_TEXT_FILE);
 }
 
+/*
+ * Planner hook: forward to regular planner, but measure planning time.
+ */
+static PlannedStmt *pgss_planner_hook(Query *parse,
+									  int cursorOptions,
+									  ParamListInfo boundParams)
+{
+	PlannedStmt *result;
+
+	if (pgss_enabled())
+	{
+		instr_time		start;
+		instr_time		duration;
+
+		INSTR_TIME_SET_CURRENT(start);
+
+		nested_level++;
+		PG_TRY();
+		{
+			if (prev_planner_hook)
+				result = prev_planner_hook(parse, cursorOptions, boundParams);
+			else
+				result = standard_planner(parse, cursorOptions, boundParams);
+			nested_level--;
+		}
+		PG_CATCH();
+		{
+			nested_level--;
+			PG_RE_THROW();
+		}
+		PG_END_TRY();
+
+		INSTR_TIME_SET_CURRENT(duration);
+		INSTR_TIME_SUBTRACT(duration, start);
+
+		result->planning_time = INSTR_TIME_GET_DOUBLE(duration);
+	}
+	else
+	{
+		if (prev_planner_hook)
+			result = prev_planner_hook(parse, cursorOptions, boundParams);
+		else
+			result = standard_planner(parse, cursorOptions, boundParams);
+	}
+
+	return result;
+}
+
 /*
  * Post-parse-analysis hook: mark query with a queryId
  */
@@ -837,6 +899,7 @@ pgss_post_parse_analyze(ParseState *pstate, Query *query)
 				   query->stmt_len,
 				   0,
 				   0,
+				   0,
 				   NULL,
 				   &jstate);
 }
@@ -943,9 +1006,16 @@ pgss_ExecutorEnd(QueryDesc *queryDesc)
 				   queryDesc->plannedstmt->stmt_location,
 				   queryDesc->plannedstmt->stmt_len,
 				   queryDesc->totaltime->total * 1000.0,	/* convert to msec */
+				   queryDesc->plannedstmt->planning_time * 1000.0,
 				   queryDesc->estate->es_processed,
 				   &queryDesc->totaltime->bufusage,
 				   NULL);
+
+		/*
+		 * Clear planning_time, so that we only count it once for each
+		 * replanning of a prepared statement.
+		 */
+		queryDesc->plannedstmt->planning_time = 0;
 	}
 
 	if (prev_ExecutorEnd)
@@ -974,8 +1044,7 @@ pgss_ProcessUtility(PlannedStmt *pstmt, const char *queryString,
 	 * hash table entry for the PREPARE (with hash calculated from the query
 	 * string), and then a different one with the same query string (but hash
 	 * calculated from the query tree) would be used to accumulate costs of
-	 * ensuing EXECUTEs.  This would be confusing, and inconsistent with other
-	 * cases where planning time is not included at all.
+	 * ensuing EXECUTEs.
 	 *
 	 * Likewise, we don't track execution of DEALLOCATE.
 	 */
@@ -1054,6 +1123,7 @@ pgss_ProcessUtility(PlannedStmt *pstmt, const char *queryString,
 				   pstmt->stmt_location,
 				   pstmt->stmt_len,
 				   INSTR_TIME_GET_MILLISEC(duration),
+				   0,
 				   rows,
 				   &bufusage,
 				   NULL);
@@ -1096,7 +1166,9 @@ pgss_hash_string(const char *str, int len)
 static void
 pgss_store(const char *query, uint64 queryId,
 		   int query_location, int query_len,
-		   double total_time, uint64 rows,
+		   double total_time,
+		   double planning_time,
+		   uint64 rows,
 		   const BufferUsage *bufusage,
 		   pgssJumbleState *jstate)
 {
@@ -1265,6 +1337,9 @@ pgss_store(const char *query, uint64 queryId,
 			if (e->counters.max_time < total_time)
 				e->counters.max_time = total_time;
 		}
+		if (planning_time > 0)
+			e->counters.plans += 1;
+		e->counters.planning_time += planning_time;
 		e->counters.rows += rows;
 		e->counters.shared_blks_hit += bufusage->shared_blks_hit;
 		e->counters.shared_blks_read += bufusage->shared_blks_read;
@@ -1310,7 +1385,8 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS)
 #define PG_STAT_STATEMENTS_COLS_V1_1	18
 #define PG_STAT_STATEMENTS_COLS_V1_2	19
 #define PG_STAT_STATEMENTS_COLS_V1_3	23
-#define PG_STAT_STATEMENTS_COLS			23	/* maximum of above */
+#define PG_STAT_STATEMENTS_COLS_V1_4	25
+#define PG_STAT_STATEMENTS_COLS			25	/* maximum of above */
 
 /*
  * Retrieve statement statistics.
@@ -1322,6 +1398,16 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS)
  * expected API version is identified by embedding it in the C name of the
  * function.  Unfortunately we weren't bright enough to do that for 1.1.
  */
+Datum
+pg_stat_statements_1_4(PG_FUNCTION_ARGS)
+{
+	bool		showtext = PG_GETARG_BOOL(0);
+
+	pg_stat_statements_internal(fcinfo, PGSS_V1_4, showtext);
+
+	return (Datum) 0;
+}
+
 Datum
 pg_stat_statements_1_3(PG_FUNCTION_ARGS)
 {
@@ -1428,6 +1514,10 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 			if (api_version != PGSS_V1_3)
 				elog(ERROR, "incorrect number of output arguments");
 			break;
+		case PG_STAT_STATEMENTS_COLS_V1_4:
+			if (api_version != PGSS_V1_4)
+				elog(ERROR, "incorrect number of output arguments");
+			break;
 		default:
 			elog(ERROR, "incorrect number of output arguments");
 	}
@@ -1586,6 +1676,11 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 		if (tmp.calls == 0)
 			continue;
 
+		if (api_version >= PGSS_V1_4)
+		{
+			values[i++] = Int64GetDatumFast(tmp.plans);
+			values[i++] = Float8GetDatumFast(tmp.planning_time);
+		}
 		values[i++] = Int64GetDatumFast(tmp.calls);
 		values[i++] = Float8GetDatumFast(tmp.total_time);
 		if (api_version >= PGSS_V1_3)
@@ -1629,6 +1724,7 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 					 api_version == PGSS_V1_1 ? PG_STAT_STATEMENTS_COLS_V1_1 :
 					 api_version == PGSS_V1_2 ? PG_STAT_STATEMENTS_COLS_V1_2 :
 					 api_version == PGSS_V1_3 ? PG_STAT_STATEMENTS_COLS_V1_3 :
+					 api_version == PGSS_V1_4 ? PG_STAT_STATEMENTS_COLS_V1_4 :
 					 -1 /* fail if you forget to update this assert */ ));
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/contrib/pg_stat_statements/pg_stat_statements.control b/contrib/pg_stat_statements/pg_stat_statements.control
index 193fcdfafa0..617038b4c05 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.control
+++ b/contrib/pg_stat_statements/pg_stat_statements.control
@@ -1,5 +1,5 @@
 # pg_stat_statements extension
 comment = 'track execution statistics of all SQL statements executed'
-default_version = '1.5'
+default_version = '1.6'
 module_pathname = '$libdir/pg_stat_statements'
 relocatable = true
diff --git a/contrib/pg_stat_statements/sql/pg_stat_statements.sql b/contrib/pg_stat_statements/sql/pg_stat_statements.sql
index a8361fd1bff..e15b789369a 100644
--- a/contrib/pg_stat_statements/sql/pg_stat_statements.sql
+++ b/contrib/pg_stat_statements/sql/pg_stat_statements.sql
@@ -195,4 +195,20 @@ DROP FUNCTION PLUS_TWO(INTEGER);
 
 SELECT query, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
 
+--
+-- [re]plan counting
+--
+SELECT pg_stat_statements_reset();
+CREATE TABLE test ();
+PREPARE prep1 AS SELECT COUNT(*) FROM test;;
+EXECUTE prep1;
+EXECUTE prep1;
+EXECUTE prep1;
+ALTER TABLE test ADD COLUMN x int;
+EXECUTE prep1;
+SELECT 42;
+SELECT 42;
+SELECT 42;
+SELECT query, plans, calls, rows FROM pg_stat_statements ORDER BY query COLLATE "C";
+
 DROP EXTENSION pg_stat_statements;
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index c0217ed485f..19b8f3bb1aa 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -9,7 +9,8 @@
 
  <para>
   The <filename>pg_stat_statements</filename> module provides a means for
-  tracking execution statistics of all SQL statements executed by a server.
+  tracking planning and execution statistics of all SQL statements executed by
+  a server.
  </para>
 
  <para>
@@ -82,6 +83,20 @@
       <entry>Text of a representative statement</entry>
      </row>
 
+     <row>
+      <entry><structfield>plans</structfield></entry>
+      <entry><type>bigint</type></entry>
+      <entry></entry>
+      <entry>Number of times the statement was planned</entry>
+     </row>
+
+     <row>
+      <entry><structfield>planning_time</structfield></entry>
+      <entry><type>double precision</type></entry>
+      <entry></entry>
+      <entry>Total time spent planning the statement, in milliseconds</entry>
+     </row>
+
      <row>
       <entry><structfield>calls</structfield></entry>
       <entry><type>bigint</type></entry>
@@ -93,35 +108,35 @@
       <entry><structfield>total_time</structfield></entry>
       <entry><type>double precision</type></entry>
       <entry></entry>
-      <entry>Total time spent in the statement, in milliseconds</entry>
+      <entry>Total time spent executing the statement, in milliseconds</entry>
      </row>
 
      <row>
       <entry><structfield>min_time</structfield></entry>
       <entry><type>double precision</type></entry>
       <entry></entry>
-      <entry>Minimum time spent in the statement, in milliseconds</entry>
+      <entry>Minimum time spent executing the statement, in milliseconds</entry>
      </row>
 
      <row>
       <entry><structfield>max_time</structfield></entry>
       <entry><type>double precision</type></entry>
       <entry></entry>
-      <entry>Maximum time spent in the statement, in milliseconds</entry>
+      <entry>Maximum time spent executing the statement, in milliseconds</entry>
      </row>
 
      <row>
       <entry><structfield>mean_time</structfield></entry>
       <entry><type>double precision</type></entry>
       <entry></entry>
-      <entry>Mean time spent in the statement, in milliseconds</entry>
+      <entry>Mean time spent executing the statement, in milliseconds</entry>
      </row>
 
      <row>
       <entry><structfield>stddev_time</structfield></entry>
       <entry><type>double precision</type></entry>
       <entry></entry>
-      <entry>Population standard deviation of time spent in the statement, in milliseconds</entry>
+      <entry>Population standard deviation of time spent executing the statement, in milliseconds</entry>
      </row>
 
      <row>
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index ddbbc79823e..35ea267a5cc 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -99,6 +99,7 @@ _copyPlannedStmt(const PlannedStmt *from)
 	COPY_NODE_FIELD(invalItems);
 	COPY_NODE_FIELD(paramExecTypes);
 	COPY_NODE_FIELD(utilityStmt);
+	COPY_SCALAR_FIELD(planning_time);
 	COPY_LOCATION_FIELD(stmt_location);
 	COPY_LOCATION_FIELD(stmt_len);
 
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 5e72df137e7..ff71b63f5b4 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -284,6 +284,7 @@ _outPlannedStmt(StringInfo str, const PlannedStmt *node)
 	WRITE_NODE_FIELD(invalItems);
 	WRITE_NODE_FIELD(paramExecTypes);
 	WRITE_NODE_FIELD(utilityStmt);
+	WRITE_FLOAT_FIELD(planning_time, "%.0f");
 	WRITE_LOCATION_FIELD(stmt_location);
 	WRITE_LOCATION_FIELD(stmt_len);
 }
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 9925866b53a..4c5d30277d1 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -1482,6 +1482,7 @@ _readPlannedStmt(void)
 	READ_NODE_FIELD(invalItems);
 	READ_NODE_FIELD(paramExecTypes);
 	READ_NODE_FIELD(utilityStmt);
+	READ_FLOAT_FIELD(planning_time);
 	READ_LOCATION_FIELD(stmt_location);
 	READ_LOCATION_FIELD(stmt_len);
 
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 7b52dadd817..05a3aacb2c0 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -478,6 +478,7 @@ standard_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
 	result->paramExecTypes = glob->paramExecTypes;
 	/* utilityStmt should be null, but we might as well copy it */
 	result->utilityStmt = parse->utilityStmt;
+	result->planning_time = 0;
 	result->stmt_location = parse->stmt_location;
 	result->stmt_len = parse->stmt_len;
 
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index 74e9fb5f7bd..f6d8c260370 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -93,6 +93,9 @@ typedef struct PlannedStmt
 
 	Node	   *utilityStmt;	/* non-null if this is utility stmt */
 
+	/* This is always set to 0 by the core system, but plugins can change it. */
+	double		planning_time;
+
 	/* statement location in source string (copied from Query) */
 	int			stmt_location;	/* start location, or -1 if unknown */
 	int			stmt_len;		/* length in bytes; 0 means "rest of string" */
-- 
2.15.1