rac2: safe format send stream stats

Add `String()` and `SafeFormat()` methods for `RangeSendStreamStats` and
`ReplicaSendStreamStats`.

Part of: #123509
Release note: None

pkg/kv/kvserver/kvflowcontrol/rac2/BUILD.bazel

@@ -29,6 +29,7 @@ go_library(
         "//pkg/util/admission/admissionpb",
         "//pkg/util/buildutil",
         "//pkg/util/hlc",
+        "//pkg/util/humanizeutil",
         "//pkg/util/log",
         "//pkg/util/metric",
         "//pkg/util/queue",

pkg/kv/kvserver/kvflowcontrol/rac2/range_controller.go

@@ -24,6 +24,7 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/util/admission/admissionpb"
 	"github.com/cockroachdb/cockroach/pkg/util/buildutil"
 	"github.com/cockroachdb/cockroach/pkg/util/hlc"
+	"github.com/cockroachdb/cockroach/pkg/util/humanizeutil"
 	"github.com/cockroachdb/cockroach/pkg/util/log"
 	"github.com/cockroachdb/cockroach/pkg/util/syncutil"
 	"github.com/cockroachdb/errors"
@@ -219,6 +220,22 @@ type RangeSendStreamStats struct {
 	internal []ReplicaSendStreamStats
 }
 
+func (s *RangeSendStreamStats) String() string {
+	return redact.StringWithoutMarkers(s)
+}
+
+// SafeFormat implements the redact.SafeFormatter interface.
+func (s *RangeSendStreamStats) SafeFormat(w redact.SafePrinter, _ rune) {
+	w.Printf("[")
+	for i := range s.internal {
+		if i > 0 {
+			w.Printf(", ")
+		}
+		w.Printf("r%v=(%v)", s.internal[i].ReplicaID, s.internal[i])
+	}
+	w.Printf("]")
+}
+
 // Clear clears the stats for all replica send streams so that the underlying
 // memory can be reused.
 func (s *RangeSendStreamStats) Clear() {
@@ -323,6 +340,15 @@ type ReplicaSendStreamStats struct {
 	ReplicaSendQueueStats
 }
 
+func (rsss ReplicaSendStreamStats) String() string {
+	return redact.StringWithoutMarkers(rsss)
+}
+
+func (rsss ReplicaSendStreamStats) SafeFormat(w redact.SafePrinter, _ rune) {
+	w.Printf("is_state_replicate=%v has_send_queue=%v %v",
+		rsss.IsStateReplicate, rsss.HasSendQueue, rsss.ReplicaSendQueueStats)
+}
+
 // ReplicaSendQueueStats contains the size and count of the send stream queue
 // for a replica.
 type ReplicaSendQueueStats struct {
@@ -333,6 +359,16 @@ type ReplicaSendQueueStats struct {
 	SendQueueCount int64
 }
 
+func (rsqs ReplicaSendQueueStats) String() string {
+	return redact.StringWithoutMarkers(rsqs)
+}
+
+// SafeFormat implements the redact.SafeFormatter interface.
+func (rsqs ReplicaSendQueueStats) SafeFormat(w redact.SafePrinter, _ rune) {
+	w.Printf("send_queue_size=%v / %v entries",
+		humanizeutil.IBytes(rsqs.SendQueueBytes), rsqs.SendQueueCount)
+}
+
 // RaftEvent carries a RACv2-relevant subset of raft state sent to storage.
 type RaftEvent struct {
 	// MsgAppMode is the current mode. This is only relevant on the leader.
@@ -1480,7 +1516,6 @@ func (rc *rangeController) SendStreamStats(statsToSet *RangeSendStreamStats) {
 	if len(statsToSet.internal) != 0 {
 		panic(errors.AssertionFailedf("statsToSet is non-empty %v", statsToSet.internal))
 	}
-	statsToSet.Clear()
 	rc.mu.RLock()
 	defer rc.mu.RUnlock()
 

pkg/kv/kvserver/kvflowcontrol/rac2/range_controller_test.go

@@ -2305,3 +2305,36 @@ func TestConstructRaftEventForReplica(t *testing.T) {
 		})
 	}
 }
+
+func TestRangeSendStreamStatsString(t *testing.T) {
+	defer leaktest.AfterTest(t)()
+	defer log.Scope(t).Close(t)
+
+	stats := RangeSendStreamStats{
+		internal: []ReplicaSendStreamStats{
+			{
+				IsStateReplicate: false,
+				HasSendQueue:     true,
+				ReplicaSendQueueStats: ReplicaSendQueueStats{
+					ReplicaID:      1,
+					SendQueueCount: 10,
+					SendQueueBytes: 100,
+				},
+			},
+			{
+				IsStateReplicate: true,
+				HasSendQueue:     false,
+				ReplicaSendQueueStats: ReplicaSendQueueStats{
+					ReplicaID:      2,
+					SendQueueCount: 0,
+					SendQueueBytes: 0,
+				},
+			},
+		},
+	}
+
+	require.Equal(t,
+		"[r1=(is_state_replicate=false has_send_queue=true send_queue_size=100 B / 10 entries), "+
+			"r2=(is_state_replicate=true has_send_queue=false send_queue_size=0 B / 0 entries)]",
+		stats.String())
+}