planner: increase default concurrency factor of cost computing (pingc…

…ap#11752)

cmd/explaintest/r/access_path_selection.result

@@ -23,24 +23,3 @@ id	count	task	operator info
 IndexReader_11	1104.45	root	index:Selection_10
 └─Selection_10	1104.45	cop	lt(test.access_path_selection.b, 3)
   └─IndexScan_9	3323.33	cop	table:access_path_selection, index:a, b, range:[-inf,3), keep order:false, stats:pseudo
-CREATE TABLE `outdated_statistics` (
-`a` int,
-`b` int,
-`c` int,
-INDEX idx_a(a),
-INDEX idx_ab(a,b)
-);
-insert into outdated_statistics values (2, 2, 2);
-insert into outdated_statistics values (3, 3, 3);
-insert into outdated_statistics values (4, 4, 4);
-analyze table outdated_statistics;
-insert into outdated_statistics values (1, 1, 1);
-insert into outdated_statistics values (1, 2, 2);
-insert into outdated_statistics values (1, 3, 3);
-analyze table outdated_statistics index idx_ab;
-explain select * from outdated_statistics where a=1 and b=1 and c=1;
-id	count	task	operator info
-IndexLookUp_11	0.00	root	
-├─IndexScan_8	1.00	cop	table:outdated_statistics, index:a, b, range:[1 1,1 1], keep order:false
-└─Selection_10	0.00	cop	eq(test.outdated_statistics.c, 1)
-  └─TableScan_9	1.00	cop	table:outdated_statistics, keep order:false

cmd/explaintest/r/explain_easy.result

@@ -365,27 +365,27 @@ Projection_10	5.00	root	9_aux_0
   ├─TableReader_14	5.00	root	data:TableScan_13
   │ └─TableScan_13	5.00	cop	table:t, range:[-inf,+inf], keep order:false
   └─StreamAgg_19	1.00	root	funcs:count(1)
-    └─IndexJoin_44	2.40	root	left outer join, inner:TableReader_43, outer key:test.s.a, inner key:test.t1.a
-      ├─IndexReader_35	2.40	root	index:Selection_34
-      │ └─Selection_34	2.40	cop	eq(3, test.t.a)
-      │   └─IndexScan_33	3.00	cop	table:s, index:b, range:[3,3], keep order:false
-      └─TableReader_43	0.80	root	data:Selection_42
-        └─Selection_42	0.80	cop	eq(3, test.t.a)
-          └─TableScan_41	1.00	cop	table:t1, range: decided by [test.s.a], keep order:false
+    └─MergeJoin_39	2.40	root	left outer join, left key:test.s.a, right key:test.t1.a
+      ├─TableReader_29	2.40	root	data:Selection_28
+      │ └─Selection_28	2.40	cop	eq(3, test.t.a), eq(test.s.b, 3)
+      │   └─TableScan_27	5.00	cop	table:s, range:[-inf,+inf], keep order:true
+      └─TableReader_32	4.00	root	data:Selection_31
+        └─Selection_31	4.00	cop	eq(3, test.t.a)
+          └─TableScan_30	5.00	cop	table:t1, range:[-inf,+inf], keep order:true
 explain select t.c in (select count(*) from t s right join t t1 on s.a = t1.a where 3 = t.a and t1.b = 3) from t;
 id	count	task	operator info
 Projection_10	5.00	root	9_aux_0
 └─Apply_12	5.00	root	CARTESIAN left outer semi join, inner:StreamAgg_19, other cond:eq(test.t.c, 7_col_0)
   ├─TableReader_14	5.00	root	data:TableScan_13
   │ └─TableScan_13	5.00	cop	table:t, range:[-inf,+inf], keep order:false
   └─StreamAgg_19	1.00	root	funcs:count(1)
-    └─IndexJoin_42	2.40	root	right outer join, inner:TableReader_41, outer key:test.t1.a, inner key:test.s.a
-      ├─TableReader_41	0.80	root	data:Selection_40
-      │ └─Selection_40	0.80	cop	eq(3, test.t.a)
-      │   └─TableScan_39	1.00	cop	table:s, range: decided by [test.t1.a], keep order:false
-      └─IndexReader_34	2.40	root	index:Selection_33
-        └─Selection_33	2.40	cop	eq(3, test.t.a)
-          └─IndexScan_32	3.00	cop	table:t1, index:b, range:[3,3], keep order:false
+    └─MergeJoin_38	2.40	root	right outer join, left key:test.s.a, right key:test.t1.a
+      ├─TableReader_28	4.00	root	data:Selection_27
+      │ └─Selection_27	4.00	cop	eq(3, test.t.a)
+      │   └─TableScan_26	5.00	cop	table:s, range:[-inf,+inf], keep order:true
+      └─TableReader_31	2.40	root	data:Selection_30
+        └─Selection_30	2.40	cop	eq(3, test.t.a), eq(test.t1.b, 3)
+          └─TableScan_29	5.00	cop	table:t1, range:[-inf,+inf], keep order:true
 drop table if exists t;
 create table t(a int unsigned);
 explain select t.a = '123455' from t;

cmd/explaintest/t/access_path_selection.test

@@ -12,26 +12,3 @@ explain select a, b from access_path_selection where a < 3;
 # In this query, IDX_ab can't be used, so IDX_b is the best.
 explain select a, b from access_path_selection where b < 3;
 explain select a, b from access_path_selection where a < 3 and b < 3;
-
-CREATE TABLE `outdated_statistics` (
-`a` int,
-`b` int,
-`c` int,
-INDEX idx_a(a),
-INDEX idx_ab(a,b)
-);
-insert into outdated_statistics values (2, 2, 2);
-insert into outdated_statistics values (3, 3, 3);
-insert into outdated_statistics values (4, 4, 4);
-analyze table outdated_statistics;
-insert into outdated_statistics values (1, 1, 1);
-insert into outdated_statistics values (1, 2, 2);
-insert into outdated_statistics values (1, 3, 3);
-# Only update idx_ab and leave idx_a outdated.
-# Then the estimated number of rows on idx_ab is 1 while it's 0 on idx_a.
-# But for this query, idx_ab is always better than idx_a,
-# because idx_a can't take column b into account while idx_ab can.
-# This wrong case can be solved by Skyline Pruning, so we may update its
-# result after Skyline Pruning is introduced.
-analyze table outdated_statistics index idx_ab;
-explain select * from outdated_statistics where a=1 and b=1 and c=1;

planner/core/cbo_test.go

@@ -281,9 +281,6 @@ func (s *testAnalyzeSuite) TestIndexRead(c *C) {
 	}
 	testKit.MustExec("analyze table t1")
 	ctx := testKit.Se.(sessionctx.Context)
-	sessionVars := ctx.GetSessionVars()
-	sessionVars.HashAggFinalConcurrency = 1
-	sessionVars.HashAggPartialConcurrency = 1
 	tests := []struct {
 		sql  string
 		best string
@@ -496,8 +493,8 @@ func (s *testAnalyzeSuite) TestAnalyze(c *C) {
 			best: "TableReader(Table(t)->Sel([le(test.t.a, 2)]))",
 		},
 		{
-			sql:  "select * from t where t.b < 2",
-			best: "IndexLookUp(Index(t.b)[[-inf,2)], Table(t))",
+			sql:  "select b from t where t.b < 2",
+			best: "IndexReader(Index(t.b)[[-inf,2)])",
 		},
 		{
 			sql:  "select * from t where t.a = 1 and t.b <= 2",
@@ -528,8 +525,8 @@ func (s *testAnalyzeSuite) TestAnalyze(c *C) {
 			best: "UnionAll{TableReader(Table(t4)->Sel([le(test.t4.a, 2)]))->TableReader(Table(t4)->Sel([le(test.t4.a, 2)]))}",
 		},
 		{
-			sql:  "select * from t4 where t4.b < 2",
-			best: "UnionAll{IndexLookUp(Index(t4.b)[[-inf,2)], Table(t4))->IndexLookUp(Index(t4.b)[[-inf,2)], Table(t4))}",
+			sql:  "select b from t4 where t4.b < 2",
+			best: "UnionAll{IndexReader(Index(t4.b)[[-inf,2)])->IndexReader(Index(t4.b)[[-inf,2)])}",
 		},
 		{
 			sql:  "select * from t4 where t4.a = 1 and t4.b <= 2",
@@ -685,13 +682,9 @@ func (s *testAnalyzeSuite) TestCorrelatedEstimation(c *C) {
 	}()
 	tk.MustExec("use test")
 	tk.MustExec("set sql_mode='STRICT_TRANS_TABLES'") // disable only full group by
-	tk.MustExec("create table t(a int, b int, c int, index idx(c))")
+	tk.MustExec("create table t(a int, b int, c int, index idx(c,b,a))")
 	tk.MustExec("insert into t values(1,1,1), (2,2,2), (3,3,3), (4,4,4), (5,5,5), (6,6,6), (7,7,7), (8,8,8), (9,9,9),(10,10,10)")
 	tk.MustExec("analyze table t")
-	ctx := tk.Se.(sessionctx.Context)
-	sessionVars := ctx.GetSessionVars()
-	sessionVars.HashAggFinalConcurrency = 1
-	sessionVars.HashAggPartialConcurrency = 1
 	tk.MustQuery("explain select t.c in (select count(*) from t s , t t1 where s.a = t.a and s.a = t1.a) from t;").
 		Check(testkit.Rows(
 			"Projection_11 10.00 root 9_aux_0",
@@ -715,10 +708,9 @@ func (s *testAnalyzeSuite) TestCorrelatedEstimation(c *C) {
 			"  │ └─TableScan_11 10.00 cop table:t, range:[-inf,+inf], keep order:false",
 			"  └─MaxOneRow_13 1.00 root ",
 			"    └─Projection_14 0.10 root concat(cast(test.t1.a), \",\", cast(test.t1.b))",
-			"      └─IndexLookUp_21 0.10 root ",
-			"        ├─IndexScan_18 1.00 cop table:t1, index:c, range: decided by [eq(test.t1.c, test.t.c)], keep order:false",
-			"        └─Selection_20 0.10 cop eq(test.t1.a, test.t.a)",
-			"          └─TableScan_19 1.00 cop table:t, keep order:false",
+			"      └─IndexReader_17 0.10 root index:Selection_16",
+			"        └─Selection_16 0.10 cop eq(test.t1.a, test.t.a)",
+			"          └─IndexScan_15 1.00 cop table:t1, index:c, b, a, range: decided by [eq(test.t1.c, test.t.c)], keep order:false",
 		))
 }
 
@@ -1085,16 +1077,16 @@ func (s *testAnalyzeSuite) TestLimitCrossEstimation(c *C) {
 	))
 	// Multi-column filter.
 	tk.MustExec("drop table t")
-	tk.MustExec("create table t(a int primary key, b int, c int, d bigint default 2147483648, e bigint default 2147483648, f bigint default 2147483648, index idx_b(b))")
+	tk.MustExec("create table t(a int primary key, b int, c int, d bigint default 2147483648, e bigint default 2147483648, f bigint default 2147483648, index idx(b,d,a,c))")
 	tk.MustExec("insert into t(a, b, c) values (1, 1, 1),(2, 1, 2),(3, 1, 1),(4, 1, 2),(5, 1, 1),(6, 1, 2),(7, 1, 1),(8, 1, 2),(9, 1, 1),(10, 1, 2),(11, 1, 1),(12, 1, 2),(13, 1, 1),(14, 1, 2),(15, 1, 1),(16, 1, 2),(17, 1, 1),(18, 1, 2),(19, 1, 1),(20, 2, 2),(21, 2, 1),(22, 2, 2),(23, 2, 1),(24, 2, 2),(25, 2, 1)")
 	tk.MustExec("analyze table t")
-	tk.MustQuery("EXPLAIN SELECT * FROM t WHERE b = 2 and c > 0 ORDER BY a limit 1").Check(testkit.Rows(
-		"TopN_9 1.00 root test.t.a:asc, offset:0, count:1",
-		"└─IndexLookUp_22 1.00 root ",
-		"  ├─IndexScan_18 6.00 cop table:t, index:b, range:[2,2], keep order:false",
-		"  └─TopN_21 1.00 cop test.t.a:asc, offset:0, count:1",
-		"    └─Selection_20 6.00 cop gt(test.t.c, 0)",
-		"      └─TableScan_19 6.00 cop table:t, keep order:false",
+	tk.MustQuery("EXPLAIN SELECT a FROM t WHERE b = 2 and c > 0 ORDER BY a limit 1").Check(testkit.Rows(
+		"Projection_7 1.00 root test.t.a",
+		"└─TopN_8 1.00 root test.t.a:asc, offset:0, count:1",
+		"  └─IndexReader_17 1.00 root index:TopN_16",
+		"    └─TopN_16 1.00 cop test.t.a:asc, offset:0, count:1",
+		"      └─Selection_15 6.00 cop gt(test.t.c, 0)",
+		"        └─IndexScan_14 6.00 cop table:t, index:b, d, a, c, range:[2,2], keep order:false",
 	))
 }
 

planner/core/find_best_task.go

@@ -37,7 +37,7 @@ const (
 	scanFactor        = 1.5 * netWorkFactor
 	descScanFactor    = 2 * scanFactor
 	memoryFactor      = 0.001
-	concurrencyFactor = 0.001
+	concurrencyFactor = 3.0
 
 	selectionFactor = 0.8
 	distinctFactor  = 0.8

planner/core/logical_plan_test.go

@@ -2249,7 +2249,7 @@ func (s *testPlanSuite) TestWindowFunction(c *C) {
 		},
 		{
 			sql:    "select sum(avg(a)) over() from t",
-			result: "TableReader(Table(t)->HashAgg)->HashAgg->Window(sum(sel_agg_2) over())->Projection",
+			result: "TableReader(Table(t)->StreamAgg)->StreamAgg->Window(sum(sel_agg_2) over())->Projection",
 		},
 		{
 			sql:    "select b from t order by(sum(a) over())",
@@ -2261,7 +2261,7 @@ func (s *testPlanSuite) TestWindowFunction(c *C) {
 		},
 		{
 			sql:    "select b from t order by(sum(avg(a)) over())",
-			result: "TableReader(Table(t)->HashAgg)->HashAgg->Window(sum(sel_agg_2) over())->Sort->Projection",
+			result: "TableReader(Table(t)->StreamAgg)->StreamAgg->Window(sum(sel_agg_2) over())->Sort->Projection",
 		},
 		{
 			sql:    "select a from t having (select sum(a) over() as w from t tt where a > t.a)",
@@ -2480,14 +2480,8 @@ func (s *testPlanSuite) TestWindowFunction(c *C) {
 	}
 
 	s.Parser.EnableWindowFunc(true)
-	sessionVars := s.ctx.GetSessionVars()
-	finalCon, partialCon := sessionVars.HashAggFinalConcurrency, sessionVars.HashAggPartialConcurrency
-	sessionVars.HashAggFinalConcurrency = 1
-	sessionVars.HashAggPartialConcurrency = 1
 	defer func() {
 		s.Parser.EnableWindowFunc(false)
-		sessionVars.HashAggFinalConcurrency = finalCon
-		sessionVars.HashAggPartialConcurrency = partialCon
 	}()
 	ctx := context.TODO()
 	for i, tt := range tests {

planner/core/physical_plan_test.go

@@ -1232,8 +1232,6 @@ func (s *testPlanSuite) TestAggEliminater(c *C) {
 	_, err = se.Execute(context.Background(), "use test")
 	c.Assert(err, IsNil)
 	se.Execute(context.Background(), "set sql_mode='STRICT_TRANS_TABLES'") // disable only full group by
-	se.GetSessionVars().HashAggFinalConcurrency = 1
-	se.GetSessionVars().HashAggPartialConcurrency = 1
 	tests := []struct {
 		sql  string
 		best string

util/ranger/ranger_test.go

@@ -1102,15 +1102,15 @@ func (s *testRangerSuite) TestCompIndexInExprCorrCol(c *C) {
 	testKit.MustExec("analyze table t")
 	testKit.MustQuery("explain select t.e in (select count(*) from t s use index(idx), t t1 where s.b = 1 and s.c in (1, 2) and s.d = t.a and s.a = t1.a) from t").Check(testkit.Rows(
 		"Projection_11 2.00 root 9_aux_0",
-		"└─Apply_13 2.00 root CARTESIAN left outer semi join, inner:HashAgg_18, other cond:eq(test.t.e, 7_col_0)",
+		"└─Apply_13 2.00 root CARTESIAN left outer semi join, inner:StreamAgg_20, other cond:eq(test.t.e, 7_col_0)",
 		"  ├─TableReader_15 2.00 root data:TableScan_14",
 		"  │ └─TableScan_14 2.00 cop table:t, range:[-inf,+inf], keep order:false",
-		"  └─HashAgg_18 1.00 root funcs:count(1)",
-		"    └─HashLeftJoin_24 2.00 root inner join, inner:TableReader_29, equal:[eq(test.s.a, test.t1.a)]",
+		"  └─StreamAgg_20 1.00 root funcs:count(1)",
+		"    └─IndexJoin_32 2.00 root inner join, inner:TableReader_31, outer key:test.s.a, inner key:test.t1.a",
 		"      ├─IndexReader_27 2.00 root index:IndexScan_26",
 		"      │ └─IndexScan_26 2.00 cop table:s, index:b, c, d, range: decided by [eq(test.s.b, 1) in(test.s.c, 1, 2) eq(test.s.d, test.t.a)], keep order:false",
-		"      └─TableReader_29 2.00 root data:TableScan_28",
-		"        └─TableScan_28 2.00 cop table:t1, range:[-inf,+inf], keep order:false",
+		"      └─TableReader_31 1.00 root data:TableScan_30",
+		"        └─TableScan_30 1.00 cop table:t1, range: decided by [test.s.a], keep order:false",
 	))
 	testKit.MustQuery("select t.e in (select count(*) from t s use index(idx), t t1 where s.b = 1 and s.c in (1, 2) and s.d = t.a and s.a = t1.a) from t").Check(testkit.Rows(
 		"1",