support set value of tidb_opt_distinct_agg_push_down in config… (ping…

…cap#16590)
glorv · Apr 22, 2020 · c28a695 · c28a695
1 parent db7c135
commit c28a695
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Showing 5 changed files with 7 additions and 2 deletions.
diff --git a/config/config.go b/config/config.go
@@ -359,6 +359,7 @@ type Performance struct {
 	TCPKeepAlive        bool    `toml:"tcp-keep-alive" json:"tcp-keep-alive"`
 	CrossJoin           bool    `toml:"cross-join" json:"cross-join"`
 	RunAutoAnalyze      bool    `toml:"run-auto-analyze" json:"run-auto-analyze"`
+	DistinctAggPushDown bool    `toml:"distinct-agg-push-down" json:"agg-push-down-join"`
 }
 
 // PlanCache is the PlanCache section of the config.
@@ -592,6 +593,7 @@ var defaultConf = Config{
 		ForcePriority:       "NO_PRIORITY",
 		BindInfoLease:       "3s",
 		TxnTotalSizeLimit:   DefTxnTotalSizeLimit,
+		DistinctAggPushDown: false,
 	},
 	ProxyProtocol: ProxyProtocol{
 		Networks:      "",

diff --git a/config/config.toml.example b/config/config.toml.example
@@ -232,6 +232,9 @@ force-priority = "NO_PRIORITY"
 # Bind info lease duration, which influences the duration of loading bind info and handling invalid bind.
 bind-info-lease = "3s"
 
+# Whether support pushing down aggregation with distinct to cop task
+distinct-agg-push-down = false
+
 # The limitation of the size in byte for the entries in one transaction.
 # If using TiKV as the storage, the entry represents a key/value pair.
 # NOTE: If binlog is enabled, this value should be less than 104857600(10M) because this is the maximum size that can be handled by Pumper.

diff --git a/sessionctx/variable/sysvar.go b/sessionctx/variable/sysvar.go
@@ -610,7 +610,7 @@ var defaultSysVars = []*SysVar{
 	/* TiDB specific variables */
 	{ScopeSession, TiDBSnapshot, ""},
 	{ScopeSession, TiDBOptAggPushDown, BoolToIntStr(DefOptAggPushDown)},
-	{ScopeSession, TiDBOptDistinctAggPushDown, BoolToIntStr(DefOptDistinctAggPushDown)},
+	{ScopeSession, TiDBOptDistinctAggPushDown, BoolToIntStr(config.GetGlobalConfig().Performance.DistinctAggPushDown)},
 	{ScopeSession, TiDBOptWriteRowID, BoolToIntStr(DefOptWriteRowID)},
 	{ScopeGlobal | ScopeSession, TiDBBuildStatsConcurrency, strconv.Itoa(DefBuildStatsConcurrency)},
 	{ScopeGlobal, TiDBAutoAnalyzeRatio, strconv.FormatFloat(DefAutoAnalyzeRatio, 'f', -1, 64)},

diff --git a/sessionctx/variable/tidb_vars.go b/sessionctx/variable/tidb_vars.go
@@ -413,7 +413,6 @@ const (
 	DefChecksumTableConcurrency        = 4
 	DefSkipUTF8Check                   = false
 	DefOptAggPushDown                  = false
-	DefOptDistinctAggPushDown          = false
 	DefOptWriteRowID                   = false
 	DefOptCorrelationThreshold         = 0.9
 	DefOptCorrelationExpFactor         = 1

diff --git a/tidb-server/main.go b/tidb-server/main.go
@@ -559,6 +559,7 @@ func setGlobalVars() {
 	priority := mysql.Str2Priority(cfg.Performance.ForcePriority)
 	variable.ForcePriority = int32(priority)
 	variable.SysVars[variable.TiDBForcePriority].Value = mysql.Priority2Str[priority]
+	variable.SysVars[variable.TiDBOptDistinctAggPushDown].Value = variable.BoolToIntStr(cfg.Performance.DistinctAggPushDown)
 
 	variable.SysVars[variable.TIDBMemQuotaQuery].Value = strconv.FormatInt(cfg.MemQuotaQuery, 10)
 	variable.SysVars["lower_case_table_names"].Value = strconv.Itoa(cfg.LowerCaseTableNames)