Fix IndexOnlyScan counter for heap fetches in parallel mode

The HeapFetches counter was using a simple value in IndexOnlyScanState,
which fails to propagate values from parallel workers; so the counts are
wrong when IndexOnlyScan runs in parallel.  Move it to Instrumentation,
like all the other counters.

While at it, change INSERT ON CONFLICT conflicting tuple counter to use
the new ntuples2 instead of nfiltered2, which is a blatant misuse.

Discussion: https://postgr.es/m/20180409215851.idwc75ct2bzi6tea@alvherre.pgsql

4 files changed, 7 insertions, 11 deletions

diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 989b6aad67b..306e6444669 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -1459,12 +1459,8 @@ ExplainNode(PlanState *planstate, List *ancestors,
 				show_instrumentation_count("Rows Removed by Filter", 1,
 										   planstate, es);
 			if (es->analyze)
-			{
-				long		heapFetches =
-					((IndexOnlyScanState *) planstate)->ioss_HeapFetches;
-
-				ExplainPropertyInteger("Heap Fetches", NULL, heapFetches, es);
-			}
+				ExplainPropertyFloat("Heap Fetches", NULL,
+									 planstate->instrument->ntuples2, 0, es);
 			break;
 		case T_BitmapIndexScan:
 			show_scan_qual(((BitmapIndexScan *) plan)->indexqualorig,
@@ -3132,7 +3128,7 @@ show_modifytable_info(ModifyTableState *mtstate, List *ancestors,
 
 			/* count the number of source rows */
 			total = mtstate->mt_plans[0]->instrument->ntuples;
-			other_path = mtstate->ps.instrument->nfiltered2;
+			other_path = mtstate->ps.instrument->ntuples2;
 			insert_path = total - other_path;
 
 			ExplainPropertyFloat("Tuples Inserted", NULL,
diff --git a/src/backend/executor/instrument.c b/src/backend/executor/instrument.c
index 86252cee1f3..fe5d55904d2 100644
--- a/src/backend/executor/instrument.c
+++ b/src/backend/executor/instrument.c
@@ -156,6 +156,7 @@ InstrAggNode(Instrumentation *dst, Instrumentation *add)
 	dst->startup += add->startup;
 	dst->total += add->total;
 	dst->ntuples += add->ntuples;
+	dst->ntuples2 += add->ntuples2;
 	dst->nloops += add->nloops;
 	dst->nfiltered1 += add->nfiltered1;
 	dst->nfiltered2 += add->nfiltered2;
diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c
index ddc0ae90615..3a02a996214 100644
--- a/src/backend/executor/nodeIndexonlyscan.c
+++ b/src/backend/executor/nodeIndexonlyscan.c
@@ -162,7 +162,7 @@ IndexOnlyNext(IndexOnlyScanState *node)
 			/*
 			 * Rats, we have to visit the heap to check visibility.
 			 */
-			node->ioss_HeapFetches++;
+			InstrCountTuples2(node, 1);
 			tuple = index_fetch_heap(scandesc);
 			if (tuple == NULL)
 				continue;		/* no visible tuple, try next index entry */
@@ -509,7 +509,6 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags)
 	indexstate->ss.ps.plan = (Plan *) node;
 	indexstate->ss.ps.state = estate;
 	indexstate->ss.ps.ExecProcNode = ExecIndexOnlyScan;
-	indexstate->ioss_HeapFetches = 0;
 
 	/*
 	 * Miscellaneous initialization
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index f47649d0517..543a735be2b 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -461,7 +461,7 @@ ExecInsert(ModifyTableState *mtstate,
 											 &conflictTid, planSlot, slot,
 											 estate, canSetTag, &returning))
 					{
-						InstrCountFiltered2(&mtstate->ps, 1);
+						InstrCountTuples2(&mtstate->ps, 1);
 						return returning;
 					}
 					else
@@ -476,7 +476,7 @@ ExecInsert(ModifyTableState *mtstate,
 					 */
 					Assert(onconflict == ONCONFLICT_NOTHING);
 					ExecCheckTIDVisible(estate, resultRelInfo, &conflictTid);
-					InstrCountFiltered2(&mtstate->ps, 1);
+					InstrCountTuples2(&mtstate->ps, 1);
 					return NULL;
 				}
 			}