Add delay time to VACUUM/ANALYZE (VERBOSE) and autovacuum logs.

Commit bb8dff9 added this information to the
pg_stat_progress_vacuum and pg_stat_progress_analyze system views.
This commit adds the same information to the output of VACUUM and
ANALYZE with the VERBOSE option and to the autovacuum logs.

Suggested-by: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/ZmaXmWDL829fzAVX%40ip-10-97-1-34.eu-west-3.compute.internal

Author: nathan-bossart

doc/src/sgml/config.sgml

@@ -8267,9 +8267,12 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         platforms.  You can use the <xref linkend="pgtesttiming"/> tool to
         measure the overhead of timing on your system.  Cost-based vacuum delay
         timing information is displayed in
-        <link linkend="vacuum-progress-reporting"><structname>pg_stat_progress_vacuum</structname></link>
-        and
-        <link linkend="analyze-progress-reporting"><structname>pg_stat_progress_analyze</structname></link>.
+        <link linkend="vacuum-progress-reporting"><structname>pg_stat_progress_vacuum</structname></link>,
+        <link linkend="analyze-progress-reporting"><structname>pg_stat_progress_analyze</structname></link>,
+        in the output of <xref linkend="sql-vacuum"/> when the
+        <literal>VERBOSE</literal> option is used, and by autovacuum for
+        auto-vacuums and auto-analyzes when
+        <xref linkend="guc-log-autovacuum-min-duration"/> is set.
         Only superusers and users with the appropriate <literal>SET</literal>
         privilege can change this setting.
        </para>

src/backend/access/heap/vacuumlazy.c

@@ -1091,6 +1091,17 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 								 istat->pages_deleted,
 								 istat->pages_free);
 			}
+			if (track_cost_delay_timing)
+			{
+				/*
+				 * We bypass the changecount mechanism because this value is
+				 * only updated by the calling process.  We also rely on the
+				 * above call to pgstat_progress_end_command() to not clear
+				 * the st_progress_param array.
+				 */
+				appendStringInfo(&buf, _("delay time: %.3f ms\n"),
+								 (double) MyBEEntry->st_progress_param[PROGRESS_VACUUM_DELAY_TIME] / 1000000.0);
+			}
 			if (track_io_timing)
 			{
 				double		read_ms = (double) (pgStatBlockReadTime - startreadtime) / 1000;

src/backend/commands/analyze.c

@@ -808,6 +808,15 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 							 get_database_name(MyDatabaseId),
 							 get_namespace_name(RelationGetNamespace(onerel)),
 							 RelationGetRelationName(onerel));
+			if (track_cost_delay_timing)
+			{
+				/*
+				 * We bypass the changecount mechanism because this value is
+				 * only updated by the calling process.
+				 */
+				appendStringInfo(&buf, _("delay time: %.3f ms\n"),
+								 (double) MyBEEntry->st_progress_param[PROGRESS_ANALYZE_DELAY_TIME] / 1000000.0);
+			}
 			if (track_io_timing)
 			{
 				double		read_ms = (double) (pgStatBlockReadTime - startreadtime) / 1000;