Fix unit tests

pump/storage/storage.go

@@ -58,6 +58,8 @@ var (
 	// save valuePointer headPointer, for binlog in vlog not after headPointer, we have save it in metadata db
 	// at start up, we can scan the vlog from headPointer and save the ts -> valuePointer to metadata db
 	headPointerKey = []byte("!binlog!headPointer")
+	// If the kv channel blocks for more than this value, turn on the slow chaser
+	slowChaserThreshold = 3 * time.Second
 )
 
 // Storage is the interface to handle binlog storage
@@ -910,7 +912,7 @@ func (a *Append) writeToValueLog(reqs chan *request) chan *request {
 			for _, req := range batch {
 				select {
 				case done <- req:
-				case <-time.After(3 * time.Second):
+				case <-time.After(slowChaserThreshold):
 					slowChaser.TurnOn(&req.valuePointer)
 					break SEND
 				}

pump/storage/storage_test.go

@@ -81,6 +81,11 @@ func (as *AppendSuit) TestNewAppend(c *check.C) {
 }
 
 func (as *AppendSuit) TestBlockedWriteKVShouldNotStopWritingVlogs(c *check.C) {
+	origThres := slowChaserThreshold
+	defer func() {
+		slowChaserThreshold = origThres
+	}()
+	slowChaserThreshold = 10 * time.Millisecond
 	// Set KVChanCapacity to be extremely small so that we can feed it up
 	store := newAppendWithOptions(c, DefaultOptions().WithKVChanCapacity(10))
 	incoming := make(chan *request, 100)
@@ -120,6 +125,11 @@ func (as *AppendSuit) TestBlockedWriteKVShouldNotStopWritingVlogs(c *check.C) {
 }
 
 func (as *AppendSuit) TestVlogsShouldBeInSyncWhenDownStreamRecovers(c *check.C) {
+	origThres := slowChaserThreshold
+	defer func() {
+		slowChaserThreshold = origThres
+	}()
+	slowChaserThreshold = 10 * time.Millisecond
 	opts := DefaultOptions().WithKVChanCapacity(10).WithValueLogFileSize(9000)
 	store := newAppendWithOptions(c, opts)
 	incoming := make(chan *request, 100)