telemetry, session: add telemetry collector for placement policies

domain/domain.go

@@ -1794,6 +1794,9 @@ func (do *Domain) MockInfoCacheAndLoadInfoSchema(is infoschema.InfoSchema) {
 
 func init() {
 	initByLDFlagsForGlobalKill()
+	telemetry.GetDomainInfoSchema = func(ctx sessionctx.Context) infoschema.InfoSchema {
+		return GetDomain(ctx).InfoSchema()
+	}
 }
 
 var (

session/session.go

@@ -3378,34 +3378,6 @@ func (s *session) GetTxnWriteThroughputSLI() *sli.TxnWriteThroughputSLI {
 	return &s.txn.writeSLI
 }
 
-var _ telemetry.TemporaryOrCacheTableFeatureChecker = &session{}
-
-// TemporaryTableExists is used by the telemetry package to avoid circle dependency.
-func (s *session) TemporaryTableExists() bool {
-	is := domain.GetDomain(s).InfoSchema()
-	for _, dbInfo := range is.AllSchemas() {
-		for _, tbInfo := range is.SchemaTables(dbInfo.Name) {
-			if tbInfo.Meta().TempTableType != model.TempTableNone {
-				return true
-			}
-		}
-	}
-	return false
-}
-
-// CachedTableExists is used by the telemetry package to avoid circle dependency.
-func (s *session) CachedTableExists() bool {
-	is := domain.GetDomain(s).InfoSchema()
-	for _, dbInfo := range is.AllSchemas() {
-		for _, tbInfo := range is.SchemaTables(dbInfo.Name) {
-			if tbInfo.Meta().TableCacheStatusType != model.TableCacheStatusDisable {
-				return true
-			}
-		}
-	}
-	return false
-}
-
 // GetInfoSchema returns snapshotInfoSchema if snapshot schema is set.
 // Transaction infoschema is returned if inside an explicit txn.
 // Otherwise the latest infoschema is returned.

telemetry/data_feature_usage.go

@@ -33,34 +33,82 @@ type featureUsage struct {
 	Txn *TxnUsage `json:"txn"`
 	// cluster index usage information
 	// key is the first 6 characters of sha2(TABLE_NAME, 256)
-	ClusterIndex   *ClusterIndexUsage `json:"clusterIndex"`
-	TemporaryTable bool               `json:"temporaryTable"`
-	CTE            *m.CTEUsageCounter `json:"cte"`
-	CachedTable    bool               `json:"cachedTable"`
-	AutoCapture    bool               `json:"autoCapture"`
+	ClusterIndex         *ClusterIndexUsage    `json:"clusterIndex"`
+	TemporaryTable       bool                  `json:"temporaryTable"`
+	CTE                  *m.CTEUsageCounter    `json:"cte"`
+	CachedTable          bool                  `json:"cachedTable"`
+	AutoCapture          bool                  `json:"autoCapture"`
+	PlacementPolicyUsage *placementPolicyUsage `json:"placementPolicy"`
+}
+
+type placementPolicyUsage struct {
+	NumPlacementPolicies uint64 `json:"numPlacementPolicies"`
+	NumDBWithPolicies    uint64 `json:"numDBWithPolicies"`
+	NumTableWithPolicies uint64 `json:"numTableWithPolicies"`
+	// The number of partitions that policies are explicitly specified.
+	NumPartitionWithExplicitPolicies uint64 `json:"numPartitionWithExplicitPolicies"`
 }
 
 func getFeatureUsage(ctx sessionctx.Context) (*featureUsage, error) {
-	clusterIdxUsage, err := getClusterIndexUsageInfo(ctx)
+	var usage featureUsage
+	var err error
+	usage.ClusterIndex, err = getClusterIndexUsageInfo(ctx)
 	if err != nil {
 		logutil.BgLogger().Info(err.Error())
 		return nil, err
 	}
 
 	// transaction related feature
-	txnUsage := getTxnUsageInfo(ctx)
+	usage.Txn = getTxnUsageInfo(ctx)
+
+	usage.CTE = getCTEUsageInfo()
 
-	// Avoid the circle dependency.
-	temporaryTable := ctx.(TemporaryOrCacheTableFeatureChecker).TemporaryTableExists()
+	usage.AutoCapture = getAutoCaptureUsageInfo(ctx)
 
-	cteUsage := getCTEUsageInfo()
+	collectFeatureUsageFromInfoschema(ctx, &usage)
+	return &usage, nil
+}
 
-	cachedTable := ctx.(TemporaryOrCacheTableFeatureChecker).CachedTableExists()
+// collectFeatureUsageFromInfoschema updates the usage for temporary table, cached table and placement policies.
+func collectFeatureUsageFromInfoschema(ctx sessionctx.Context, usage *featureUsage) {
+	if usage.PlacementPolicyUsage == nil {
+		usage.PlacementPolicyUsage = &placementPolicyUsage{}
+	}
+	is := GetDomainInfoSchema(ctx)
+	for _, dbInfo := range is.AllSchemas() {
+		if dbInfo.PlacementPolicyRef != nil {
+			usage.PlacementPolicyUsage.NumDBWithPolicies++
+		}
 
-	enableAutoCapture := getAutoCaptureUsageInfo(ctx)
-	return &featureUsage{txnUsage, clusterIdxUsage, temporaryTable, cteUsage, cachedTable, enableAutoCapture}, nil
+		for _, tbInfo := range is.SchemaTables(dbInfo.Name) {
+			if tbInfo.Meta().TempTableType != model.TempTableNone {
+				usage.TemporaryTable = true
+			}
+			if tbInfo.Meta().TableCacheStatusType != model.TableCacheStatusDisable {
+				usage.CachedTable = true
+			}
+			if tbInfo.Meta().PlacementPolicyRef != nil {
+				usage.PlacementPolicyUsage.NumTableWithPolicies++
+			}
+			partitions := tbInfo.Meta().GetPartitionInfo()
+			if partitions == nil {
+				continue
+			}
+			for _, partitionInfo := range partitions.Definitions {
+				if partitionInfo.PlacementPolicyRef != nil {
+					usage.PlacementPolicyUsage.NumPartitionWithExplicitPolicies++
+				}
+			}
+		}
+	}
+
+	usage.PlacementPolicyUsage.NumPlacementPolicies += uint64(len(is.AllPlacementPolicies()))
 }
 
+// GetDomainInfoSchema is used by the telemetry package to get the latest schema information
+// while avoiding circle dependency with domain package.
+var GetDomainInfoSchema func(sessionctx.Context) infoschema.InfoSchema
+
 // ClusterIndexUsage records the usage info of all the tables, no more than 10k tables
 type ClusterIndexUsage map[string]TableClusteredInfo
 
@@ -139,13 +187,6 @@ func getClusterIndexUsageInfo(ctx sessionctx.Context) (cu *ClusterIndexUsage, er
 	return &usage, nil
 }
 
-// TemporaryOrCacheTableFeatureChecker is defined to avoid package circle dependency.
-// The session struct implements this interface.
-type TemporaryOrCacheTableFeatureChecker interface {
-	TemporaryTableExists() bool
-	CachedTableExists() bool
-}
-
 // TxnUsage records the usage info of transaction related features, including
 // async-commit, 1PC and counters of transactions committed with different protocols.
 type TxnUsage struct {

telemetry/data_feature_usage_test.go

@@ -126,6 +126,49 @@ func TestCachedTable(t *testing.T) {
 	require.False(t, usage.CachedTable)
 }
 
+func TestPlacementPolicies(t *testing.T) {
+	store, clean := testkit.CreateMockStore(t)
+	defer clean()
+
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+
+	usage, err := telemetry.GetFeatureUsage(tk.Session())
+	require.NoError(t, err)
+	require.Equal(t, uint64(0), usage.PlacementPolicyUsage.NumPlacementPolicies)
+	require.Equal(t, uint64(0), usage.PlacementPolicyUsage.NumDBWithPolicies)
+	require.Equal(t, uint64(0), usage.PlacementPolicyUsage.NumTableWithPolicies)
+	require.Equal(t, uint64(0), usage.PlacementPolicyUsage.NumPartitionWithExplicitPolicies)
+
+	tk.MustExec("create placement policy p1 followers=4;")
+	tk.MustExec(`create placement policy p2 primary_region="cn-east-1" regions="cn-east-1,cn-east"`)
+	tk.MustExec(`create placement policy p3 followers=3`)
+	tk.MustExec("alter database test placement policy=p1;")
+	tk.MustExec("create table t1(a int);")
+	tk.MustExec("create table t2(a int) placement policy=p2;")
+	tk.MustExec("create table t3(id int) PARTITION BY RANGE (id) (" +
+		"PARTITION p0 VALUES LESS THAN (100) placement policy p3," +
+		"PARTITION p1 VALUES LESS THAN (1000))")
+
+	usage, err = telemetry.GetFeatureUsage(tk.Session())
+	require.NoError(t, err)
+	require.Equal(t, uint64(3), usage.PlacementPolicyUsage.NumPlacementPolicies)
+	require.Equal(t, uint64(1), usage.PlacementPolicyUsage.NumDBWithPolicies)
+	require.Equal(t, uint64(3), usage.PlacementPolicyUsage.NumTableWithPolicies)
+	require.Equal(t, uint64(1), usage.PlacementPolicyUsage.NumPartitionWithExplicitPolicies)
+
+	tk.MustExec("drop table t2;")
+	tk.MustExec("drop placement policy p2;")
+	tk.MustExec("alter table t3 placement policy=default")
+
+	usage, err = telemetry.GetFeatureUsage(tk.Session())
+	require.NoError(t, err)
+	require.Equal(t, uint64(2), usage.PlacementPolicyUsage.NumPlacementPolicies)
+	require.Equal(t, uint64(1), usage.PlacementPolicyUsage.NumDBWithPolicies)
+	require.Equal(t, uint64(1), usage.PlacementPolicyUsage.NumTableWithPolicies)
+	require.Equal(t, uint64(1), usage.PlacementPolicyUsage.NumPartitionWithExplicitPolicies)
+}
+
 func TestAutoCapture(t *testing.T) {
 	store, clean := testkit.CreateMockStore(t)
 	defer clean()