planner: remove unused binding metrics (#51665)

ref #51347

Author: qw4990

pkg/bindinfo/binding.go

@@ -18,7 +18,6 @@ import (
 	"time"
 	"unsafe"
 
-	"github.com/pingcap/tidb/pkg/metrics"
 	"github.com/pingcap/tidb/pkg/parser"
 	"github.com/pingcap/tidb/pkg/parser/ast"
 	"github.com/pingcap/tidb/pkg/sessionctx"
@@ -224,47 +223,8 @@ func (br Bindings) size() float64 {
 	return mem
 }
 
-var statusIndex = map[string]int{
-	Enabled: 0,
-	deleted: 1,
-	Invalid: 2,
-}
-
-func bindingMetrics(br Bindings) ([]float64, []int) {
-	sizes := make([]float64, len(statusIndex))
-	count := make([]int, len(statusIndex))
-	if br == nil {
-		return sizes, count
-	}
-	commonLength := float64(0)
-	// We treat it as deleted if there are no bindings. It could only occur in session handles.
-	if len(br) == 0 {
-		sizes[statusIndex[deleted]] = commonLength
-		count[statusIndex[deleted]] = 1
-		return sizes, count
-	}
-	// Make the common length counted in the first binding.
-	sizes[statusIndex[br[0].Status]] = commonLength
-	for _, binding := range br {
-		sizes[statusIndex[binding.Status]] += binding.size()
-		count[statusIndex[binding.Status]]++
-	}
-	return sizes, count
-}
-
 // size calculates the memory size of a bind info.
 func (b *Binding) size() float64 {
 	res := len(b.OriginalSQL) + len(b.Db) + len(b.BindSQL) + len(b.Status) + 2*int(unsafe.Sizeof(b.CreateTime)) + len(b.Charset) + len(b.Collation) + len(b.ID)
 	return float64(res)
 }
-
-func updateMetrics(scope string, before Bindings, after Bindings, sizeOnly bool) {
-	beforeSize, beforeCount := bindingMetrics(before)
-	afterSize, afterCount := bindingMetrics(after)
-	for status, index := range statusIndex {
-		metrics.BindMemoryUsage.WithLabelValues(scope, status).Add(afterSize[index] - beforeSize[index])
-		if !sizeOnly {
-			metrics.BindTotalGauge.WithLabelValues(scope, status).Add(float64(afterCount[index] - beforeCount[index]))
-		}
-	}
-}

pkg/bindinfo/global_handle.go

@@ -23,7 +23,6 @@ import (
 	"time"
 
 	"github.com/pingcap/errors"
-	"github.com/pingcap/tidb/pkg/metrics"
 	"github.com/pingcap/tidb/pkg/parser"
 	"github.com/pingcap/tidb/pkg/parser/ast"
 	"github.com/pingcap/tidb/pkg/parser/format"
@@ -243,7 +242,6 @@ func (h *globalBindingHandle) LoadFromStorageToCache(fullLoad bool) (err error)
 			} else {
 				newCache.RemoveBinding(sqlDigest)
 			}
-			updateMetrics(metrics.ScopeGlobal, oldBinding, newCache.GetBinding(sqlDigest), true)
 		}
 		return nil
 	})

pkg/bindinfo/global_handle_test.go

@@ -23,7 +23,6 @@ import (
 	"github.com/pingcap/tidb/pkg/bindinfo"
 	"github.com/pingcap/tidb/pkg/bindinfo/internal"
 	"github.com/pingcap/tidb/pkg/bindinfo/norm"
-	"github.com/pingcap/tidb/pkg/metrics"
 	"github.com/pingcap/tidb/pkg/parser"
 	sessiontypes "github.com/pingcap/tidb/pkg/session/types"
 	"github.com/pingcap/tidb/pkg/testkit"
@@ -425,9 +424,6 @@ func TestGlobalBinding(t *testing.T) {
 		tk.MustExec("create table t1(i int, s varchar(20))")
 		tk.MustExec("create index index_t on t(i,s)")
 
-		metrics.BindTotalGauge.Reset()
-		metrics.BindMemoryUsage.Reset()
-
 		_, err := tk.Exec("create global " + testSQL.createSQL)
 		require.NoError(t, err, "err %v", err)
 

pkg/bindinfo/session_handle.go

@@ -21,7 +21,6 @@ import (
 	"time"
 
 	"github.com/pingcap/errors"
-	"github.com/pingcap/tidb/pkg/metrics"
 	"github.com/pingcap/tidb/pkg/parser"
 	"github.com/pingcap/tidb/pkg/parser/ast"
 	"github.com/pingcap/tidb/pkg/parser/mysql"
@@ -68,12 +67,10 @@ func NewSessionBindingHandle() SessionBindingHandle {
 // appendSessionBinding adds the Bindings to the cache, all the stale bindMetas are
 // removed from the cache after this operation.
 func (h *sessionBindingHandle) appendSessionBinding(sqlDigest string, meta Bindings) {
-	oldBindings := h.ch.GetBinding(sqlDigest)
 	err := h.ch.SetBinding(sqlDigest, meta)
 	if err != nil {
 		logutil.BgLogger().Warn("SessionHandle.appendSessionBinding", zap.String("category", "sql-bind"), zap.Error(err))
 	}
-	updateMetrics(metrics.ScopeSession, oldBindings, meta, false)
 }
 
 // CreateSessionBinding creates a Bindings to the cache.
@@ -146,9 +143,7 @@ func (h *sessionBindingHandle) DecodeSessionStates(_ context.Context, sctx sessi
 }
 
 // Close closes the session handle.
-func (h *sessionBindingHandle) Close() {
-	updateMetrics(metrics.ScopeSession, h.ch.GetAllBindings(), nil, false)
-}
+func (*sessionBindingHandle) Close() {}
 
 // sessionBindInfoKeyType is a dummy type to avoid naming collision in context.
 type sessionBindInfoKeyType int

pkg/bindinfo/session_handle_test.go

@@ -91,9 +91,6 @@ func TestSessionBinding(t *testing.T) {
 		tk.MustExec("create table t1(i int, s varchar(20))")
 		tk.MustExec("create index index_t on t(i,s)")
 
-		metrics.BindTotalGauge.Reset()
-		metrics.BindMemoryUsage.Reset()
-
 		_, err := tk.Exec("create session " + testSQL.createSQL)
 		require.NoError(t, err, "err %v", err)
 
@@ -102,14 +99,6 @@ func TestSessionBinding(t *testing.T) {
 			require.NoError(t, err)
 		}
 
-		pb := &dto.Metric{}
-		err = metrics.BindTotalGauge.WithLabelValues(metrics.ScopeSession, bindinfo.Enabled).Write(pb)
-		require.NoError(t, err)
-		require.Equal(t, float64(1), pb.GetGauge().GetValue())
-		err = metrics.BindMemoryUsage.WithLabelValues(metrics.ScopeSession, bindinfo.Enabled).Write(pb)
-		require.NoError(t, err)
-		require.Equal(t, testSQL.memoryUsage, pb.GetGauge().GetValue())
-
 		handle := tk.Session().Value(bindinfo.SessionBindInfoKeyType).(bindinfo.SessionBindingHandle)
 		stmt, err := parser.New().ParseOneStmt(testSQL.originSQL, "", "")
 		require.NoError(t, err)

pkg/metrics/bindinfo.go

@@ -19,8 +19,6 @@ import "github.com/prometheus/client_golang/prometheus"
 // bindinfo metrics.
 var (
 	BindUsageCounter *prometheus.CounterVec
-	BindTotalGauge   *prometheus.GaugeVec
-	BindMemoryUsage  *prometheus.GaugeVec
 )
 
 // InitBindInfoMetrics initializes bindinfo metrics.
@@ -32,20 +30,4 @@ func InitBindInfoMetrics() {
 			Name:      "bind_usage_counter",
 			Help:      "Counter of query using sql bind",
 		}, []string{LabelScope})
-
-	BindTotalGauge = NewGaugeVec(
-		prometheus.GaugeOpts{
-			Namespace: "tidb",
-			Subsystem: "bindinfo",
-			Name:      "bind_total_gauge",
-			Help:      "Total number of sql bind",
-		}, []string{LabelScope, LblType})
-
-	BindMemoryUsage = NewGaugeVec(
-		prometheus.GaugeOpts{
-			Namespace: "tidb",
-			Subsystem: "bindinfo",
-			Name:      "bind_memory_usage",
-			Help:      "Memory usage of sql bind",
-		}, []string{LabelScope, LblType})
 }

pkg/metrics/metrics.go

@@ -124,8 +124,6 @@ func RegisterMetrics() {
 	prometheus.MustRegister(AutoIDHistogram)
 	prometheus.MustRegister(BatchAddIdxHistogram)
 	prometheus.MustRegister(BindUsageCounter)
-	prometheus.MustRegister(BindTotalGauge)
-	prometheus.MustRegister(BindMemoryUsage)
 	prometheus.MustRegister(CampaignOwnerCounter)
 	prometheus.MustRegister(ConnGauge)
 	prometheus.MustRegister(DisconnectionCounter)