etcd/tests/robustness/traffic/traffic.go

// Copyright 2022 The etcd Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package traffic

import (
	"context"
	"sync"
	"testing"
	"time"

	"go.uber.org/zap"
	"golang.org/x/time/rate"

	"go.etcd.io/etcd/tests/v3/framework/e2e"
	"go.etcd.io/etcd/tests/v3/robustness/failpoint"
	"go.etcd.io/etcd/tests/v3/robustness/identity"
	"go.etcd.io/etcd/tests/v3/robustness/model"
	"go.etcd.io/etcd/tests/v3/robustness/report"
)

var (
	DefaultLeaseTTL   int64 = 7200
	RequestTimeout          = 40 * time.Millisecond
	WatchTimeout            = 400 * time.Millisecond
	MultiOpTxnOpCount       = 4

	LowTraffic = Profile{
		Name:                           "LowTraffic",
		MinimalQPS:                     100,
		MaximalQPS:                     200,
		ClientCount:                    8,
		MaxNonUniqueRequestConcurrency: 3,
	}
	HighTrafficProfile = Profile{
		Name:                           "HighTraffic",
		MinimalQPS:                     200,
		MaximalQPS:                     1000,
		ClientCount:                    12,
		MaxNonUniqueRequestConcurrency: 3,
	}
)

func SimulateTraffic(ctx context.Context, t *testing.T, lg *zap.Logger, clus *e2e.EtcdProcessCluster, profile Profile, traffic Traffic, failpointInjected <-chan failpoint.InjectionReport, baseTime time.Time, ids identity.Provider) []report.ClientReport {
	mux := sync.Mutex{}
	endpoints := clus.EndpointsGRPC()

	lm := identity.NewLeaseIDStorage()
	reports := []report.ClientReport{}
	limiter := rate.NewLimiter(rate.Limit(profile.MaximalQPS), 200)

	cc, err := NewClient(endpoints, ids, baseTime)
	if err != nil {
		t.Fatal(err)
	}
	defer cc.Close()
	// Ensure that first operation succeeds
	_, err = cc.Put(ctx, "start", "true")
	if err != nil {
		t.Fatalf("First operation failed, validation requires first operation to succeed, err: %s", err)
	}
	wg := sync.WaitGroup{}
	nonUniqueWriteLimiter := NewConcurrencyLimiter(profile.MaxNonUniqueRequestConcurrency)
	finish := make(chan struct{})
	lg.Info("Start traffic")
	startTime := time.Since(baseTime)
	for i := 0; i < profile.ClientCount; i++ {
		wg.Add(1)
		c, nerr := NewClient([]string{endpoints[i%len(endpoints)]}, ids, baseTime)
		if nerr != nil {
			t.Fatal(nerr)
		}
		go func(c *RecordingClient) {
			defer wg.Done()
			defer c.Close()

			traffic.Run(ctx, c, limiter, ids, lm, nonUniqueWriteLimiter, finish)
			mux.Lock()
			reports = append(reports, c.Report())
			mux.Unlock()
		}(c)
	}
	var fr *failpoint.InjectionReport
	select {
	case frp, ok := <-failpointInjected:
		if !ok {
			t.Fatalf("Failed to collect failpoint report")
		}
		fr = &frp
	case <-ctx.Done():
		t.Fatalf("Traffic finished before failure was injected: %s", ctx.Err())
	}
	close(finish)
	wg.Wait()
	lg.Info("Finished traffic")
	endTime := time.Since(baseTime)

	time.Sleep(time.Second)
	// Ensure that last operation succeeds
	_, err = cc.Put(ctx, "tombstone", "true")
	if err != nil {
		t.Fatalf("Last operation failed, validation requires last operation to succeed, err: %s", err)
	}
	reports = append(reports, cc.Report())

	totalStats := calculateStats(reports, startTime, endTime)
	beforeFailpointStats := calculateStats(reports, startTime, fr.Start)
	duringFailpointStats := calculateStats(reports, fr.Start, fr.End)
	afterFailpointStats := calculateStats(reports, fr.End, endTime)

	lg.Info("Reporting complete traffic", zap.Int("successes", totalStats.successes), zap.Int("failures", totalStats.failures), zap.Float64("successRate", totalStats.successRate()), zap.Duration("period", totalStats.period), zap.Float64("qps", totalStats.QPS()))
	lg.Info("Reporting traffic before failure injection", zap.Int("successes", beforeFailpointStats.successes), zap.Int("failures", beforeFailpointStats.failures), zap.Float64("successRate", beforeFailpointStats.successRate()), zap.Duration("period", beforeFailpointStats.period), zap.Float64("qps", beforeFailpointStats.QPS()))
	lg.Info("Reporting traffic during failure injection", zap.Int("successes", duringFailpointStats.successes), zap.Int("failures", duringFailpointStats.failures), zap.Float64("successRate", duringFailpointStats.successRate()), zap.Duration("period", duringFailpointStats.period), zap.Float64("qps", duringFailpointStats.QPS()))
	lg.Info("Reporting traffic after failure injection", zap.Int("successes", afterFailpointStats.successes), zap.Int("failures", afterFailpointStats.failures), zap.Float64("successRate", afterFailpointStats.successRate()), zap.Duration("period", afterFailpointStats.period), zap.Float64("qps", afterFailpointStats.QPS()))

	if beforeFailpointStats.QPS() < profile.MinimalQPS {
		t.Errorf("Requiring minimal %f qps before failpoint injection for test results to be reliable, got %f qps", profile.MinimalQPS, beforeFailpointStats.QPS())
	}
	// TODO: Validate QPS post failpoint injection to ensure the that we sufficiently cover period when cluster recovers.
	return reports
}

func calculateStats(reports []report.ClientReport, start, end time.Duration) (ts trafficStats) {
	ts.period = end - start

	for _, r := range reports {
		for _, op := range r.KeyValue {
			if op.Call < start.Nanoseconds() || op.Call > end.Nanoseconds() {
				continue
			}
			resp := op.Output.(model.MaybeEtcdResponse)
			if resp.Error == "" {
				ts.successes++
			} else {
				ts.failures++
			}
		}
	}
	return ts
}

type trafficStats struct {
	successes, failures int
	period              time.Duration
}

func (ts *trafficStats) successRate() float64 {
	return float64(ts.successes) / float64(ts.successes+ts.failures)
}

func (ts *trafficStats) QPS() float64 {
	return float64(ts.successes) / ts.period.Seconds()
}

type Profile struct {
	Name                           string
	MinimalQPS                     float64
	MaximalQPS                     float64
	MaxNonUniqueRequestConcurrency int
	ClientCount                    int
}

type Traffic interface {
	Run(ctx context.Context, c *RecordingClient, qpsLimiter *rate.Limiter, ids identity.Provider, lm identity.LeaseIDStorage, nonUniqueWriteLimiter ConcurrencyLimiter, finish <-chan struct{})
	ExpectUniqueRevision() bool
	Name() string
}