0003-Add-backend_type-column-in-pg_stat_get_activity.patch

From c59011315e90b8558ca80e835068e9c5f8cc1ac2 Mon Sep 17 00:00:00 2001
From: Kuntal Ghosh <kuntal.ghosh@enterprisedb.com>
Date: Wed, 15 Mar 2017 12:53:11 +0530
Subject: [PATCH 3/3] Add backend_type column in pg_stat_get_activity

backend_type indicates the type of process in the stat table.
---
 doc/src/sgml/monitoring.sgml         | 14 ++++++++++++--
 src/backend/catalog/system_views.sql |  3 ++-
 src/backend/utils/adt/pgstatfuncs.c  |  5 ++++-
 src/include/catalog/pg_proc.h        |  2 +-
 src/test/regress/expected/rules.out  |  9 +++++----
 5 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index dcb2d33..f77c5a7 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -620,8 +620,7 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
     <row>
      <entry><structfield>backend_start</></entry>
      <entry><type>timestamp with time zone</></entry>
-     <entry>Time when this process was started, i.e., when the
-      client connected to the server
+     <entry>Time when this process was started.
      </entry>
     </row>
     <row>
@@ -797,6 +796,17 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       <xref linkend="guc-track-activity-query-size">.
      </entry>
     </row>
+    <row>
+     <entry><structfield>backend_type</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Type of current backend. Possible types are 
+      <literal>autovacuum launcher</>, <literal>autovacuum worker</>,
+      <literal>background worker</>, <literal>background writer</>,
+      <literal>client backend</>, <literal>checkpointer</>,
+      <literal>startup</>, <literal>walreceiver</>,
+      <literal>walsender</> and <literal>walwriter</>.
+     </entry>
+    </row>
    </tbody>
    </tgroup>
   </table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index b6552da..bdbb5b8 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -684,7 +684,8 @@ CREATE VIEW pg_stat_activity AS
             S.state,
             S.backend_xid,
             s.backend_xmin,
-            S.query
+            S.query,
+            S.backend_type
     FROM pg_stat_get_activity(NULL) AS S
         LEFT JOIN pg_database AS D ON (S.datid = D.oid)
         LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 96a1188..0085335 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -539,7 +539,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_activity(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_ACTIVITY_COLS	23
+#define PG_STAT_GET_ACTIVITY_COLS	24
 	int			num_backends = pgstat_fetch_stat_numbackends();
 	int			curr_backend;
 	int			pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -819,6 +819,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 					nulls[14] = true;
 				}
 			}
+			/* Add backend type */
+			values[23] = CStringGetTextDatum(pgstat_get_backend_desc(beentry->st_backendType));
 		}
 		else
 		{
@@ -834,6 +836,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
 			nulls[12] = true;
 			nulls[13] = true;
 			nulls[14] = true;
+			nulls[23] = true;
 		}
 
 		tuplestore_putvalues(tupstore, tupdesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 836d6ff..8494648 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2797,7 +2797,7 @@ DATA(insert OID = 3057 ( pg_stat_get_autoanalyze_count PGNSP PGUID 12 1 0 0 0 f
 DESCR("statistics: number of auto analyzes for a table");
 DATA(insert OID = 1936 (  pg_stat_get_backend_idset		PGNSP PGUID 12 1 100 0 0 f f f f t t s r 0 0 23 "" _null_ _null_ _null_ _null_ _null_ pg_stat_get_backend_idset _null_ _null_ _null_ ));
 DESCR("statistics: currently active backend IDs");
-DATA(insert OID = 2022 (  pg_stat_get_activity			PGNSP PGUID 12 1 100 0 0 f f f f f t s r 1 0 2249 "23" "{23,26,23,26,25,25,25,25,25,1184,1184,1184,1184,869,25,23,28,28,16,25,25,23,16,25}" "{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,ssl,sslversion,sslcipher,sslbits,sslcompression,sslclientdn}" _null_ _null_ pg_stat_get_activity _null_ _null_ _null_ ));
+DATA(insert OID = 2022 (  pg_stat_get_activity			PGNSP PGUID 12 1 100 0 0 f f f f f t s r 1 0 2249 "23" "{23,26,23,26,25,25,25,25,25,1184,1184,1184,1184,869,25,23,28,28,16,25,25,23,16,25,25}" "{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,ssl,sslversion,sslcipher,sslbits,sslcompression,sslclientdn,backend_type}" _null_ _null_ pg_stat_get_activity _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active backends");
 DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0 f f f f t t s r 1 0 2249 "25" "{25,23,26,26,20,20,20,20,20,20,20,20,20,20}" "{i,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{cmdtype,pid,datid,relid,param1,param2,param3,param4,param5,param6,param7,param8,param9,param10}" _null_ _null_ pg_stat_get_progress_info _null_ _null_ _null_ ));
 DESCR("statistics: information about progress of backends running maintenance command");
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index bd13ae6..a317bff 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1704,8 +1704,9 @@ pg_stat_activity| SELECT s.datid,
     s.state,
     s.backend_xid,
     s.backend_xmin,
-    s.query
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn)
+    s.query,
+    s.backend_type
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn, backend_type)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1833,7 +1834,7 @@ pg_stat_replication| SELECT s.pid,
     w.replay_location,
     w.sync_priority,
     w.sync_state
-   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn)
+   FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn, backend_type)
      JOIN pg_stat_get_wal_senders() w(pid, state, sent_location, write_location, flush_location, replay_location, sync_priority, sync_state) ON ((s.pid = w.pid)))
      LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
 pg_stat_ssl| SELECT s.pid,
@@ -1843,7 +1844,7 @@ pg_stat_ssl| SELECT s.pid,
     s.sslbits AS bits,
     s.sslcompression AS compression,
     s.sslclientdn AS clientdn
-   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn);
+   FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, ssl, sslversion, sslcipher, sslbits, sslcompression, sslclientdn, backend_type);
 pg_stat_subscription| SELECT su.oid AS subid,
     su.subname,
     st.pid,
-- 
1.8.3.1