pg_stat_statements: Add local_blk_{read|write}_time

This commit adds to pg_stat_statements the two new fields for local
buffers introduced by 295c36c0c1, adding the time spent to read and
write these blocks.  These are similar to what is done for temp and
shared blocks.  This information available only if track_io_timing is
enabled.

Like for 5a3423ad8e, no version bump is required in the module.

Author: Nazir Bilal Yavuz
Reviewed-by: Robert Haas, Melanie Plageman
Discussion: https://postgr.es/m/CAN55FZ19Ss279mZuqGbuUNxka0iPbLgYuOQXqAKewrjNrp27VA@mail.gmail.com

contrib/pg_stat_statements/expected/oldextversions.out

@@ -286,6 +286,8 @@ AlTER EXTENSION pg_stat_statements UPDATE TO '1.11';
  temp_blks_written      | bigint           |           |          | 
  shared_blk_read_time   | double precision |           |          | 
  shared_blk_write_time  | double precision |           |          | 
+ local_blk_read_time    | double precision |           |          | 
+ local_blk_write_time   | double precision |           |          | 
  temp_blk_read_time     | double precision |           |          | 
  temp_blk_write_time    | double precision |           |          | 
  wal_records            | bigint           |           |          | 

contrib/pg_stat_statements/pg_stat_statements--1.10--1.11.sql

@@ -43,6 +43,8 @@ CREATE FUNCTION pg_stat_statements(IN showtext boolean,
     OUT temp_blks_written int8,
     OUT shared_blk_read_time float8,
     OUT shared_blk_write_time float8,
+    OUT local_blk_read_time float8,
+    OUT local_blk_write_time float8,
     OUT temp_blk_read_time float8,
     OUT temp_blk_write_time float8,
     OUT wal_records int8,

contrib/pg_stat_statements/pg_stat_statements.c

@@ -184,6 +184,10 @@ typedef struct Counters
 										 * in msec */
 	double		shared_blk_write_time;	/* time spent writing shared blocks,
 										 * in msec */
+	double		local_blk_read_time;	/* time spent reading local blocks, in
+										 * msec */
+	double		local_blk_write_time;	/* time spent writing local blocks, in
+										 * msec */
 	double		temp_blk_read_time; /* time spent reading temp blocks, in msec */
 	double		temp_blk_write_time;	/* time spent writing temp blocks, in
 										 * msec */
@@ -1395,6 +1399,8 @@ pgss_store(const char *query, uint64 queryId,
 		e->counters.temp_blks_written += bufusage->temp_blks_written;
 		e->counters.shared_blk_read_time += INSTR_TIME_GET_MILLISEC(bufusage->shared_blk_read_time);
 		e->counters.shared_blk_write_time += INSTR_TIME_GET_MILLISEC(bufusage->shared_blk_write_time);
+		e->counters.local_blk_read_time += INSTR_TIME_GET_MILLISEC(bufusage->local_blk_read_time);
+		e->counters.local_blk_write_time += INSTR_TIME_GET_MILLISEC(bufusage->local_blk_write_time);
 		e->counters.temp_blk_read_time += INSTR_TIME_GET_MILLISEC(bufusage->temp_blk_read_time);
 		e->counters.temp_blk_write_time += INSTR_TIME_GET_MILLISEC(bufusage->temp_blk_write_time);
 		e->counters.usage += USAGE_EXEC(total_time);
@@ -1472,8 +1478,8 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS)
 #define PG_STAT_STATEMENTS_COLS_V1_8	32
 #define PG_STAT_STATEMENTS_COLS_V1_9	33
 #define PG_STAT_STATEMENTS_COLS_V1_10	43
-#define PG_STAT_STATEMENTS_COLS_V1_11	45
+#define PG_STAT_STATEMENTS_COLS_V1_11	47
-#define PG_STAT_STATEMENTS_COLS			45	/* maximum of above */
+#define PG_STAT_STATEMENTS_COLS			47	/* maximum of above */
 
 /*
  * Retrieve statement statistics.
@@ -1828,6 +1834,11 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 			values[i++] = Float8GetDatumFast(tmp.shared_blk_read_time);
 			values[i++] = Float8GetDatumFast(tmp.shared_blk_write_time);
 		}
+		if (api_version >= PGSS_V1_11)
+		{
+			values[i++] = Float8GetDatumFast(tmp.local_blk_read_time);
+			values[i++] = Float8GetDatumFast(tmp.local_blk_write_time);
+		}
 		if (api_version >= PGSS_V1_10)
 		{
 			values[i++] = Float8GetDatumFast(tmp.temp_blk_read_time);

doc/src/sgml/pgstatstatements.sgml

@@ -353,6 +353,26 @@
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>local_blk_read_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Total time the statement spent reading local blocks, in milliseconds
+       (if <xref linkend="guc-track-io-timing"/> is enabled, otherwise zero)
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>local_blk_write_time</structfield> <type>double precision</type>
+      </para>
+      <para>
+       Total time the statement spent writing local blocks, in milliseconds
+       (if <xref linkend="guc-track-io-timing"/> is enabled, otherwise zero)
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>temp_blk_read_time</structfield> <type>double precision</type>