Golang timer.Now函數代碼示例

func (l *L1L2BatchOrca) Prepend(req common.SetRequest) error {
	//log.Println("prepend", string(req.Key))

	metrics.IncCounter(MetricCmdPrependL2)
	start := timer.Now()

	err := l.l2.Prepend(req)

	metrics.ObserveHist(HistPrependL2, timer.Since(start))

	if err != nil {
		// Prepending in L2 did not succeed. Don't try in L1 since this means L2
		// may not have succeeded.
		if err == common.ErrItemNotStored {
			metrics.IncCounter(MetricCmdPrependNotStoredL2)
			metrics.IncCounter(MetricCmdPrependNotStored)
			return err
		}

		metrics.IncCounter(MetricCmdPrependErrorsL2)
		metrics.IncCounter(MetricCmdPrependErrors)
		return err
	}

	// L2 succeeded, so it's time to try L1. If L1 fails with a not found, we're
	// still good since L1 is allowed to not have the data when L2 does. If
	// there's an error, we need to fail because we're not in an unknown state
	// where L1 possibly doesn't have the Prepend when L2 does. We don't recover
	// from this but instead fail the request and let the client retry.
	metrics.IncCounter(MetricCmdPrependL1)
	start = timer.Now()

	err = l.l1.Prepend(req)

	metrics.ObserveHist(HistPrependL1, timer.Since(start))

	if err != nil {
		// Not stored in L1 is still fine. There's a possibility that a
		// concurrent delete happened or that the data has just been pushed out
		// of L1. Prepend will not bring data back into L1 as it's not necessarily
		// going to be immediately read.
		if err == common.ErrItemNotStored || err == common.ErrKeyNotFound {
			metrics.IncCounter(MetricCmdPrependNotStoredL1)
			metrics.IncCounter(MetricCmdPrependStored)
			return l.res.Prepend(req.Opaque, req.Quiet)
		}

		metrics.IncCounter(MetricCmdPrependErrorsL1)
		metrics.IncCounter(MetricCmdPrependErrors)
		return err
	}

	metrics.IncCounter(MetricCmdPrependStoredL1)
	metrics.IncCounter(MetricCmdPrependStored)
	return l.res.Prepend(req.Opaque, req.Quiet)
}

func (l *L1L2BatchOrca) Add(req common.SetRequest) error {
	//log.Println("add", string(req.Key))

	// Add in L2 first, since it has the larger state
	metrics.IncCounter(MetricCmdAddL2)
	start := timer.Now()

	err := l.l2.Add(req)

	metrics.ObserveHist(HistAddL2, timer.Since(start))

	if err != nil {
		// A key already existing is not an error per se, it's a part of the
		// functionality of the add command to respond with a "not stored" in
		// the form of a ErrKeyExists. Hence no error metrics.
		if err == common.ErrKeyExists {
			metrics.IncCounter(MetricCmdAddNotStoredL2)
			metrics.IncCounter(MetricCmdAddNotStored)
			return err
		}

		// otherwise we have a real error on our hands
		metrics.IncCounter(MetricCmdAddErrorsL2)
		metrics.IncCounter(MetricCmdAddErrors)
		return err
	}

	metrics.IncCounter(MetricCmdAddStoredL2)

	// Replace the entry in L1.
	metrics.IncCounter(MetricCmdAddReplaceL1)
	start = timer.Now()

	err = l.l1.Replace(req)

	metrics.ObserveHist(HistReplaceL1, timer.Since(start))

	if err != nil {
		if err == common.ErrKeyNotFound {
			// For a replace not stored in L1, there's no problem.
			// There is no hot data to replace
			metrics.IncCounter(MetricCmdAddReplaceNotStoredL1)
		} else {
			metrics.IncCounter(MetricCmdAddReplaceErrorsL1)
			metrics.IncCounter(MetricCmdAddErrors)
			return err
		}
	} else {
		metrics.IncCounter(MetricCmdAddReplaceStoredL1)
	}

	metrics.IncCounter(MetricCmdAddStored)

	return l.res.Add(req.Opaque, req.Quiet)
}

func (l *L1L2Orca) Set(req common.SetRequest) error {
	//log.Println("set", string(req.Key))

	// Try L2 first
	metrics.IncCounter(MetricCmdSetL2)
	start := timer.Now()

	err := l.l2.Set(req)

	metrics.ObserveHist(HistSetL2, timer.Since(start))

	// If we fail to set in L2, don't set in L1
	if err != nil {
		metrics.IncCounter(MetricCmdSetErrorsL2)
		metrics.IncCounter(MetricCmdSetErrors)
		return err
	}
	metrics.IncCounter(MetricCmdSetSuccessL2)

	// Now set in L1. If L1 fails, we log the error and fail the request.
	// If a user was writing a new piece of information, the error would be OK,
	// since the next GET would be able to put the L2 information back into L1.
	// In the case that the user was overwriting information, a failed set in L1
	// and successful one in L2 would leave us inconsistent. If the response was
	// positive in this situation, it would look like the server successfully
	// processed the request but didn't store the information. Clients will
	// retry failed writes. In this case L2 will get two writes for the same key
	// but this is better because it is more correct overall, though less
	// efficient. Note there are no retries at this level.
	//
	// It should be noted that errors on a straight set are nearly always fatal
	// for the connection. It's likely that if this branch is taken that the
	// connections to everyone will be severed (for this one client connection)
	// and that the client will reconnect to try again.
	metrics.IncCounter(MetricCmdSetL1)
	start = timer.Now()

	err = l.l1.Set(req)

	metrics.ObserveHist(HistSetL1, timer.Since(start))

	if err != nil {
		metrics.IncCounter(MetricCmdSetErrorsL1)
		metrics.IncCounter(MetricCmdSetErrors)
		return err
	}

	metrics.IncCounter(MetricCmdSetSuccessL1)
	metrics.IncCounter(MetricCmdSetSuccess)

	return l.res.Set(req.Opaque, req.Quiet)
}

func TestMonoTimeIsNeverTheSame(t *testing.T) {
	prev := timer.Now()
	same := 0

	for i := 0; i < 100000000; i++ {
		now := timer.Now()
		if now == prev {
			same++
		}
		prev = now
	}

	t.Logf("Times were the same %d times", same)
}

func (l *L1OnlyOrca) Touch(req common.TouchRequest) error {
	//log.Println("touch", string(req.Key))

	metrics.IncCounter(MetricCmdTouchL1)
	start := timer.Now()

	err := l.l1.Touch(req)

	metrics.ObserveHist(HistTouchL1, timer.Since(start))

	if err == nil {
		metrics.IncCounter(MetricCmdTouchHitsL1)
		metrics.IncCounter(MetricCmdTouchHits)

		l.res.Touch(req.Opaque)

	} else if err == common.ErrKeyNotFound {
		metrics.IncCounter(MetricCmdTouchMissesL1)
		metrics.IncCounter(MetricCmdTouchMisses)
	} else {
		metrics.IncCounter(MetricCmdTouchMissesL1)
		metrics.IncCounter(MetricCmdTouchMisses)
	}

	return err
}

func (l *L1OnlyOrca) Gat(req common.GATRequest) error {
	//log.Println("gat", string(req.Key))

	metrics.IncCounter(MetricCmdGatL1)
	start := timer.Now()

	res, err := l.l1.GAT(req)

	metrics.ObserveHist(HistGatL1, timer.Since(start))

	if err == nil {
		if res.Miss {
			metrics.IncCounter(MetricCmdGatMissesL1)
			// TODO: Account for L2
			metrics.IncCounter(MetricCmdGatMisses)
		} else {
			metrics.IncCounter(MetricCmdGatHits)
			metrics.IncCounter(MetricCmdGatHitsL1)
		}
		l.res.GAT(res)
		// There is no GetEnd call required here since this is only ever
		// done in the binary protocol, where there's no END marker.
		// Calling l.res.GetEnd was a no-op here and is just useless.
		//l.res.GetEnd(0, false)
	} else {
		metrics.IncCounter(MetricCmdGatErrors)
		metrics.IncCounter(MetricCmdGatErrorsL1)
	}

	return err
}

func main() {
	var prot common.Prot
	if f.Binary {
		prot = binprot.BinProt{}
	} else {
		prot = textprot.TextProt{}
	}

	wg := new(sync.WaitGroup)
	wg.Add(f.NumWorkers)

	extraOps := f.NumOps % f.NumWorkers
	opsPerWorker := f.NumOps / f.NumWorkers

	start := timer.Now()

	// spawn worker goroutines
	for i := 0; i < f.NumWorkers; i++ {
		numops := opsPerWorker
		if i == 0 {
			numops += extraOps
		}

		go worker(numops, prot, wg)
	}

	wg.Wait()

	log.Println("Total comm time:", timer.Since(start))
}

func (l *L1OnlyOrca) Add(req common.SetRequest) error {
	//log.Println("add", string(req.Key))

	metrics.IncCounter(MetricCmdAddL1)
	start := timer.Now()

	err := l.l1.Add(req)

	metrics.ObserveHist(HistAddL1, timer.Since(start))

	if err == nil {
		metrics.IncCounter(MetricCmdAddStoredL1)
		metrics.IncCounter(MetricCmdAddStored)

		err = l.res.Add(req.Opaque, req.Quiet)

	} else if err == common.ErrKeyExists {
		metrics.IncCounter(MetricCmdAddNotStoredL1)
		metrics.IncCounter(MetricCmdAddNotStored)
	} else {
		metrics.IncCounter(MetricCmdAddErrorsL1)
		metrics.IncCounter(MetricCmdAddErrors)
	}

	return err
}

func (l *L1OnlyOrca) Replace(req common.SetRequest) error {
	//log.Println("replace", string(req.Key))

	metrics.IncCounter(MetricCmdReplaceL1)
	start := timer.Now()

	err := l.l1.Replace(req)

	metrics.ObserveHist(HistReplaceL1, timer.Since(start))

	if err == nil {
		metrics.IncCounter(MetricCmdReplaceStoredL1)
		metrics.IncCounter(MetricCmdReplaceStored)

		err = l.res.Replace(req.Opaque, req.Quiet)

	} else if err == common.ErrKeyNotFound {
		metrics.IncCounter(MetricCmdReplaceNotStoredL1)
		metrics.IncCounter(MetricCmdReplaceNotStored)
	} else {
		metrics.IncCounter(MetricCmdReplaceErrorsL1)
		metrics.IncCounter(MetricCmdReplaceErrors)
	}

	return err
}

func (l *L1OnlyOrca) Delete(req common.DeleteRequest) error {
	//log.Println("delete", string(req.Key))

	metrics.IncCounter(MetricCmdDeleteL1)
	start := timer.Now()

	err := l.l1.Delete(req)

	metrics.ObserveHist(HistDeleteL1, timer.Since(start))

	if err == nil {
		metrics.IncCounter(MetricCmdDeleteHits)
		metrics.IncCounter(MetricCmdDeleteHitsL1)

		l.res.Delete(req.Opaque)

	} else if err == common.ErrKeyNotFound {
		metrics.IncCounter(MetricCmdDeleteMissesL1)
		metrics.IncCounter(MetricCmdDeleteMisses)
	} else {
		metrics.IncCounter(MetricCmdDeleteErrorsL1)
		metrics.IncCounter(MetricCmdDeleteErrors)
	}

	return err
}

func TestRegularIntervalsTimer(t *testing.T) {
	for i := 0; i < 100; i++ {
		start := timer.Now()
		time.Sleep(10 * time.Millisecond)
		dur := timer.Since(start)
		t.Logf("10 ms sleep took %d nanoseconds with timer", dur)
	}
}

func (l *L1L2BatchOrca) Set(req common.SetRequest) error {
	//log.Println("set", string(req.Key))

	// Try L2 first
	metrics.IncCounter(MetricCmdSetL2)
	start := timer.Now()

	err := l.l2.Set(req)

	metrics.ObserveHist(HistSetL2, timer.Since(start))

	// If we fail to set in L2, don't do anything in L1
	if err != nil {
		metrics.IncCounter(MetricCmdSetErrorsL2)
		metrics.IncCounter(MetricCmdSetErrors)
		return err
	}
	metrics.IncCounter(MetricCmdSetSuccessL2)

	// Replace the entry in L1.
	metrics.IncCounter(MetricCmdSetReplaceL1)
	start = timer.Now()

	err = l.l1.Replace(req)

	metrics.ObserveHist(HistReplaceL1, timer.Since(start))

	if err != nil {
		if err == common.ErrKeyNotFound {
			// For a replace not stored in L1, there's no problem.
			// There is no hot data to replace
			metrics.IncCounter(MetricCmdSetReplaceNotStoredL1)
		} else {
			metrics.IncCounter(MetricCmdSetReplaceErrorsL1)
			metrics.IncCounter(MetricCmdSetErrors)
			return err
		}
	} else {
		metrics.IncCounter(MetricCmdSetReplaceStoredL1)
	}

	metrics.IncCounter(MetricCmdSetSuccess)

	return l.res.Set(req.Opaque, req.Quiet)
}

func communicator(prot common.Prot, conn net.Conn, tasks <-chan *common.Task, metrics chan<- metric, comms *sync.WaitGroup) {
	r := rand.New(rand.NewSource(common.RandSeed()))
	rw := bufio.NewReadWriter(bufio.NewReader(conn), bufio.NewWriter(conn))

	for item := range tasks {
		var err error
		start := timer.Now()

		switch item.Cmd {
		case common.Set:
			err = prot.Set(rw, item.Key, item.Value)
		case common.Add:
			err = prot.Add(rw, item.Key, item.Value)
		case common.Replace:
			err = prot.Replace(rw, item.Key, item.Value)
		case common.Append:
			err = prot.Append(rw, item.Key, item.Value)
		case common.Prepend:
			err = prot.Prepend(rw, item.Key, item.Value)
		case common.Get:
			_, err = prot.Get(rw, item.Key)
		case common.Gat:
			_, err = prot.GAT(rw, item.Key)
		case common.Bget:
			bk := batchkeys(r, item.Key)
			_, err = prot.BatchGet(rw, bk)
			bkpool.Put(bk)
		case common.Delete:
			err = prot.Delete(rw, item.Key)
		case common.Touch:
			err = prot.Touch(rw, item.Key)
		}

		if err != nil {
			// don't print get misses, adds not stored, and replaces not stored
			if !isMiss(err) {
				fmt.Printf("Error performing operation %s on key %s: %s\n", item.Cmd, item.Key, err.Error())
			}
			// if the socket was closed, stop. Otherwise keep on hammering.
			if err == io.EOF {
				break
			}
		}

		m := metricPool.Get().(metric)
		m.d = timer.Since(start)
		m.op = item.Cmd
		m.miss = isMiss(err)
		metrics <- m

		taskPool.Put(item)
	}

	conn.Close()
	comms.Done()
}

func TestMonotonicAndWallTimerDifference(t *testing.T) {
	start := time.Now().UnixNano()
	monostart := timer.Now()

	for i := 0; i < 10; i++ {
		diff := time.Now().UnixNano() - start
		monodiff := timer.Since(monostart)

		t.Logf("Wall: %d", diff)
		t.Logf("Mono: %d", monodiff)

		time.Sleep(1 * time.Second)
	}
}

func (l *L1OnlyOrca) Set(req common.SetRequest) error {
	//log.Println("set", string(req.Key))

	metrics.IncCounter(MetricCmdSetL1)
	start := timer.Now()

	err := l.l1.Set(req)

	metrics.ObserveHist(HistSetL1, timer.Since(start))

	if err == nil {
		metrics.IncCounter(MetricCmdSetSuccessL1)
		metrics.IncCounter(MetricCmdSetSuccess)

		err = l.res.Set(req.Opaque, req.Quiet)

	} else {
		metrics.IncCounter(MetricCmdSetErrorsL1)
		metrics.IncCounter(MetricCmdSetErrors)
	}

	return err
}