[CF 5593] v3 - allow extensions to set a plan identifier

This branch was automatically generated by a robot using patches from an
email thread registered at:

https://commitfest.postgresql.org/patch/5593

The branch will be overwritten each time a new patch version is posted to
the thread, and also periodically to check for bitrot caused by changes
on the master branch.

Patch(es): https://www.postgresql.org/message-id/[email protected]
Author(s): Sami Imseih

Author: Commitfest Bot

src/backend/executor/execParallel.c

@@ -175,6 +175,7 @@ ExecSerializePlan(Plan *plan, EState *estate)
 	pstmt = makeNode(PlannedStmt);
 	pstmt->commandType = CMD_SELECT;
 	pstmt->queryId = pgstat_get_my_query_id();
+	pstmt->planId = pgstat_get_my_plan_id();
 	pstmt->hasReturning = false;
 	pstmt->hasModifyingCTE = false;
 	pstmt->canSetTag = true;

src/backend/optimizer/plan/planner.c

@@ -58,6 +58,7 @@
 #include "parser/parsetree.h"
 #include "partitioning/partdesc.h"
 #include "rewrite/rewriteManip.h"
+#include "utils/backend_status.h"
 #include "utils/lsyscache.h"
 #include "utils/rel.h"
 #include "utils/selfuncs.h"
@@ -291,6 +292,9 @@ planner(Query *parse, const char *query_string, int cursorOptions,
 		result = (*planner_hook) (parse, query_string, cursorOptions, boundParams);
 	else
 		result = standard_planner(parse, query_string, cursorOptions, boundParams);
+
+	pgstat_report_plan_id(result->planId, false);
+
 	return result;
 }
 

src/backend/tcop/postgres.c

@@ -1107,6 +1107,7 @@ exec_simple_query(const char *query_string)
 		size_t		cmdtaglen;
 
 		pgstat_report_query_id(0, true);
+		pgstat_report_plan_id(0, true);
 
 		/*
 		 * Get the command name for use in status display (it also becomes the
@@ -2030,6 +2031,18 @@ exec_bind_message(StringInfo input_message)
 					  cplan,
 					  psrc);
 
+	/* Portal is defined, set the plan ID based on its contents. */
+	foreach(lc, portal->stmts)
+	{
+		PlannedStmt *plan = lfirst_node(PlannedStmt, lc);
+
+		if (plan->planId != UINT64CONST(0))
+		{
+			pgstat_report_plan_id(plan->planId, false);
+			break;
+		}
+	}
+
 	/* Done with the snapshot used for parameter I/O and parsing/planning */
 	if (snapshot_set)
 		PopActiveSnapshot();
@@ -2170,6 +2183,17 @@ exec_execute_message(const char *portal_name, long max_rows)
 		}
 	}
 
+	foreach(lc, portal->stmts)
+	{
+		PlannedStmt *stmt = lfirst_node(PlannedStmt, lc);
+
+		if (stmt->planId != UINT64CONST(0))
+		{
+			pgstat_report_plan_id(stmt->planId, false);
+			break;
+		}
+	}
+
 	cmdtagname = GetCommandTagNameAndLen(portal->commandTag, &cmdtaglen);
 
 	set_ps_display_with_len(cmdtagname, cmdtaglen);

src/backend/utils/activity/backend_status.c

@@ -321,6 +321,7 @@ pgstat_bestart_initial(void)
 	lbeentry.st_progress_command = PROGRESS_COMMAND_INVALID;
 	lbeentry.st_progress_command_target = InvalidOid;
 	lbeentry.st_query_id = UINT64CONST(0);
+	lbeentry.st_plan_id = UINT64CONST(0);
 
 	/*
 	 * we don't zero st_progress_param here to save cycles; nobody should
@@ -599,6 +600,7 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 			/* st_xact_start_timestamp and wait_event_info are also disabled */
 			beentry->st_xact_start_timestamp = 0;
 			beentry->st_query_id = UINT64CONST(0);
+			beentry->st_plan_id = UINT64CONST(0);
 			proc->wait_event_info = 0;
 			PGSTAT_END_WRITE_ACTIVITY(beentry);
 		}
@@ -659,7 +661,10 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
 	 * identifier.
 	 */
 	if (state == STATE_RUNNING)
+	{
 		beentry->st_query_id = UINT64CONST(0);
+		beentry->st_plan_id = UINT64CONST(0);
+	}
 
 	if (cmd_str != NULL)
 	{
@@ -710,6 +715,44 @@ pgstat_report_query_id(uint64 query_id, bool force)
 	PGSTAT_END_WRITE_ACTIVITY(beentry);
 }
 
+/* --------
+ * pgstat_report_plan_id() -
+ *
+ * Called to update top-level plan identifier.
+ * --------
+ */
+void
+pgstat_report_plan_id(uint64 plan_id, bool force)
+{
+	volatile PgBackendStatus *beentry = MyBEEntry;
+
+	/*
+	 * if track_activities is disabled, st_plan_id should already have been
+	 * reset
+	 */
+	if (!beentry || !pgstat_track_activities)
+		return;
+
+	/*
+	 * We only report the top-level plan identifiers.  The stored plan_id is
+	 * reset when a backend calls pgstat_report_activity(STATE_RUNNING), or
+	 * with an explicit call to this function using the force flag.  If the
+	 * saved plan identifier is not zero it means that it's not a top-level
+	 * command, so ignore the one provided unless it's an explicit call to
+	 * reset the identifier.
+	 */
+	if (beentry->st_plan_id != 0 && !force)
+		return;
+
+	/*
+	 * Update my status entry, following the protocol of bumping
+	 * st_changecount before and after.  We use a volatile pointer here to
+	 * ensure the compiler doesn't try to get cute.
+	 */
+	PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
+	beentry->st_plan_id = plan_id;
+	PGSTAT_END_WRITE_ACTIVITY(beentry);
+}
 
 /* ----------
  * pgstat_report_appname() -
@@ -1106,6 +1149,21 @@ pgstat_get_my_query_id(void)
 	return MyBEEntry->st_query_id;
 }
 
+/* ----------
+ * pgstat_get_my_plan_id() -
+ *
+ * Return current backend's plan identifier.
+ */
+uint64
+pgstat_get_my_plan_id(void)
+{
+	if (!MyBEEntry)
+		return 0;
+
+	/* No need for a lock, for roughly the same reasons as above. */
+	return MyBEEntry->st_plan_id;
+}
+
 /* ----------
  * pgstat_get_backend_type_by_proc_number() -
  *

src/include/nodes/plannodes.h

@@ -55,6 +55,9 @@ typedef struct PlannedStmt
 	/* query identifier (copied from Query) */
 	uint64		queryId;
 
+	/* plan identifier (can be set by plugins) */
+	uint64		planId;
+
 	/* is it insert|update|delete|merge RETURNING? */
 	bool		hasReturning;
 

src/include/utils/backend_status.h

@@ -171,6 +171,9 @@ typedef struct PgBackendStatus
 
 	/* query identifier, optionally computed using post_parse_analyze_hook */
 	uint64		st_query_id;
+
+	/* plan identifier, optionally computed using planner_hook */
+	uint64		st_plan_id;
 } PgBackendStatus;
 
 
@@ -319,13 +322,15 @@ extern void pgstat_clear_backend_activity_snapshot(void);
 /* Activity reporting functions */
 extern void pgstat_report_activity(BackendState state, const char *cmd_str);
 extern void pgstat_report_query_id(uint64 query_id, bool force);
+extern void pgstat_report_plan_id(uint64 plan_id, bool force);
 extern void pgstat_report_tempfile(size_t filesize);
 extern void pgstat_report_appname(const char *appname);
 extern void pgstat_report_xact_timestamp(TimestampTz tstamp);
 extern const char *pgstat_get_backend_current_activity(int pid, bool checkUser);
 extern const char *pgstat_get_crashed_backend_activity(int pid, char *buffer,
 													   int buflen);
 extern uint64 pgstat_get_my_query_id(void);
+extern uint64 pgstat_get_my_plan_id(void);
 extern BackendType pgstat_get_backend_type_by_proc_number(ProcNumber procNumber);