Merge pull request #1153 from ydb-platform/last-usage

added lastUsage locked time

Author: asmyasnikov

CHANGELOG.md

@@ -1,3 +1,5 @@
+* Fixed updating last usage timestamp for smart parking of the conns
+
 ## v3.59.0
 * Added `Struct` support for `ydb.ParamsBuilder()`
 * Added support of `TzDate`,`TzDateTime`,`TzTimestamp` types in `ydb.ParamsBuilder()`

internal/conn/conn.go

@@ -7,6 +7,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/jonboulle/clockwork"
 	"github.com/ydb-platform/ydb-go-genproto/protos/Ydb"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/connectivity"
@@ -55,7 +56,7 @@ type conn struct {
 	endpoint          endpoint.Endpoint // ro access
 	closed            bool
 	state             atomic.Uint32
-	lastUsage         time.Time
+	lastUsage         *lastUsage
 	onClose           []func(*conn)
 	onTransportErrors []func(ctx context.Context, cc Conn, cause error)
 }
@@ -80,7 +81,7 @@ func (c *conn) LastUsage() time.Time {
 	c.mtx.RLock()
 	defer c.mtx.RUnlock()
 
-	return c.lastUsage
+	return c.lastUsage.Get()
 }
 
 func (c *conn) IsState(states ...State) bool {
@@ -244,12 +245,6 @@ func (c *conn) onTransportError(ctx context.Context, cause error) {
 	}
 }
 
-func (c *conn) touchLastUsage() {
-	c.mtx.Lock()
-	defer c.mtx.Unlock()
-	c.lastUsage = time.Now()
-}
-
 func isAvailable(raw *grpc.ClientConn) bool {
 	return raw != nil && raw.GetState() == connectivity.Ready
 }
@@ -332,8 +327,7 @@ func (c *conn) Invoke(
 		return c.wrapError(err)
 	}
 
-	c.touchLastUsage()
-	defer c.touchLastUsage()
+	defer c.lastUsage.Lock()()
 
 	ctx, traceID, err := meta.TraceID(ctx)
 	if err != nil {
@@ -418,8 +412,7 @@ func (c *conn) NewStream(
 		return nil, c.wrapError(err)
 	}
 
-	c.touchLastUsage()
-	defer c.touchLastUsage()
+	defer c.lastUsage.Lock()()
 
 	ctx, traceID, err := meta.TraceID(ctx)
 	if err != nil {
@@ -494,10 +487,15 @@ func withOnTransportError(onTransportError func(ctx context.Context, cc Conn, ca
 }
 
 func newConn(e endpoint.Endpoint, config Config, opts ...option) *conn {
+	clock := clockwork.NewRealClock()
 	c := &conn{
 		endpoint: e,
 		config:   config,
 		done:     make(chan struct{}),
+		lastUsage: &lastUsage{
+			t:     clock.Now(),
+			clock: clock,
+		},
 	}
 	c.state.Store(uint32(Created))
 	for _, opt := range opts {

internal/conn/grpc_client_stream.go

@@ -30,6 +30,8 @@ func (s *grpcClientStream) CloseSend() (err error) {
 		onDone(err)
 	}()
 
+	defer s.c.lastUsage.Lock()()
+
 	err = s.ClientStream.CloseSend()
 
 	if err != nil {
@@ -59,6 +61,8 @@ func (s *grpcClientStream) SendMsg(m interface{}) (err error) {
 		onDone(err)
 	}()
 
+	defer s.c.lastUsage.Lock()()
+
 	err = s.ClientStream.SendMsg(m)
 
 	if err != nil {
@@ -96,6 +100,8 @@ func (s *grpcClientStream) RecvMsg(m interface{}) (err error) {
 		onDone(err)
 	}()
 
+	defer s.c.lastUsage.Lock()()
+
 	defer func() {
 		if err != nil {
 			md := s.ClientStream.Trailer()

internal/conn/last_usage.go

@@ -0,0 +1,45 @@
+package conn
+
+import (
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/jonboulle/clockwork"
+
+	"github.com/ydb-platform/ydb-go-sdk/v3/internal/xsync"
+)
+
+type lastUsage struct {
+	locks atomic.Int64
+	mu    xsync.RWMutex
+	t     time.Time
+	clock clockwork.Clock
+}
+
+func (l *lastUsage) Get() time.Time {
+	if l.locks.CompareAndSwap(0, 1) {
+		defer func() {
+			l.locks.Add(-1)
+		}()
+
+		l.mu.RLock()
+		defer l.mu.RUnlock()
+
+		return l.t
+	}
+
+	return l.clock.Now()
+}
+
+func (l *lastUsage) Lock() (releaseFunc func()) {
+	l.locks.Add(1)
+
+	return sync.OnceFunc(func() {
+		if l.locks.Add(-1) == 0 {
+			l.mu.WithLock(func() {
+				l.t = l.clock.Now()
+			})
+		}
+	})
+}

internal/conn/last_usage_test.go

@@ -0,0 +1,97 @@
+package conn
+
+import (
+	"testing"
+	"time"
+
+	"github.com/jonboulle/clockwork"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_lastUsage_Lock(t *testing.T) {
+	t.Run("NowFromLocked", func(t *testing.T) {
+		start := time.Unix(0, 0)
+		clock := clockwork.NewFakeClockAt(start)
+		lu := &lastUsage{
+			t:     start,
+			clock: clock,
+		}
+		t1 := lu.Get()
+		require.Equal(t, start, t1)
+		f := lu.Lock()
+		clock.Advance(time.Hour)
+		t2 := lu.Get()
+		require.Equal(t, start.Add(time.Hour), t2)
+		clock.Advance(time.Hour)
+		f()
+		t3 := lu.Get()
+		require.Equal(t, start.Add(2*time.Hour), t3)
+		clock.Advance(time.Hour)
+		t4 := lu.Get()
+		require.Equal(t, start.Add(2*time.Hour), t4)
+	})
+	t.Run("UpdateAfterLastUnlock", func(t *testing.T) {
+		start := time.Unix(0, 0)
+		clock := clockwork.NewFakeClockAt(start)
+		lu := &lastUsage{
+			t:     start,
+			clock: clock,
+		}
+		t1 := lu.Get()
+		require.Equal(t, start, t1)
+		f1 := lu.Lock()
+		clock.Advance(time.Hour)
+		t2 := lu.Get()
+		require.Equal(t, start.Add(time.Hour), t2)
+		f2 := lu.Lock()
+		clock.Advance(time.Hour)
+		f1()
+		f3 := lu.Lock()
+		clock.Advance(time.Hour)
+		t3 := lu.Get()
+		require.Equal(t, start.Add(3*time.Hour), t3)
+		clock.Advance(time.Hour)
+		t4 := lu.Get()
+		require.Equal(t, start.Add(4*time.Hour), t4)
+		f3()
+		t5 := lu.Get()
+		require.Equal(t, start.Add(4*time.Hour), t5)
+		clock.Advance(time.Hour)
+		t6 := lu.Get()
+		require.Equal(t, start.Add(5*time.Hour), t6)
+		clock.Advance(time.Hour)
+		f2()
+		t7 := lu.Get()
+		require.Equal(t, start.Add(6*time.Hour), t7)
+		clock.Advance(time.Hour)
+		f2()
+		t8 := lu.Get()
+		require.Equal(t, start.Add(6*time.Hour), t8)
+	})
+	t.Run("DeferRelease", func(t *testing.T) {
+		start := time.Unix(0, 0)
+		clock := clockwork.NewFakeClockAt(start)
+		lu := &lastUsage{
+			t:     start,
+			clock: clock,
+		}
+		func() {
+			t1 := lu.Get()
+			require.Equal(t, start, t1)
+			clock.Advance(time.Hour)
+			t2 := lu.Get()
+			require.Equal(t, start, t2)
+			clock.Advance(time.Hour)
+			defer lu.Lock()()
+			t3 := lu.Get()
+			require.Equal(t, start.Add(2*time.Hour), t3)
+			clock.Advance(time.Hour)
+			t4 := lu.Get()
+			require.Equal(t, start.Add(3*time.Hour), t4)
+			clock.Advance(time.Hour)
+		}()
+		clock.Advance(time.Hour)
+		t5 := lu.Get()
+		require.Equal(t, start.Add(4*time.Hour), t5)
+	})
+}