Merge pull request #30 from robaho/master

several improvements to your great app

.gitignore

@@ -0,0 +1,3 @@
+.DS_Store
+.vscode/launch.json
+go-wrk

README.md

@@ -41,21 +41,30 @@ Command line parameters (./go-wrk -help)
 Basic Usage
 -----------
 
-    ./go-wrk -c 80 -d 5  http://192.168.1.118:8080/json
+    ./go-wrk -c 2048 -d 10 http://localhost:8080/plaintext
 
-This runs a benchmark for 5 seconds, using 80 go routines (connections)
+This runs a benchmark for 10 seconds, using 2048 go routines (connections)
 
 Output:
 
-    Running 10s test @ http://192.168.1.118:8080/json
-      80 goroutine(s) running concurrently
-       142470 requests in 4.949028953s, 19.57MB read
-         Requests/sec:		28787.47
-         Transfer/sec:		3.95MB
-         Avg Req Time:		0.0347ms
-         Fastest Request:	0.0340ms
-         Slowest Request:	0.0421ms
-         Number of Errors:	0
+    Running 10s test @ http://localhost:8080/plaintext
+        2048 goroutine(s) running concurrently
+    439977 requests in 10.012950719s, 52.45MB read
+    Requests/sec:		43940.79
+    Transfer/sec:		5.24MB
+    Fastest Request:	98µs
+    Avg Req Time:		46.608ms
+    Slowest Request:	398.431ms
+    Number of Errors:	0
+    Error Counts:		map[]
+    10%:			    164µs
+    50%:			    2.382ms
+    75%:			    3.83ms
+    99%:			    5.403ms
+    99.9%:			    5.488ms
+    99.9999%:		    5.5ms
+    99.99999%:		    5.5ms
+    stddev:			    29.744ms
 
 
 Benchmarking Tips

go-wrk.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"time"
 
+	histo "github.com/HdrHistogram/hdrhistogram-go"
 	"github.com/tsliwowicz/go-wrk/loader"
 	"github.com/tsliwowicz/go-wrk/util"
 )
@@ -38,6 +39,7 @@ var clientCert string
 var clientKey string
 var caCert string
 var http2 bool
+var cpus int = 0
 
 func init() {
 	flag.BoolVar(&versionFlag, "v", false, "Print version details")
@@ -49,6 +51,7 @@ func init() {
 	flag.IntVar(&goroutines, "c", 10, "Number of goroutines to use (concurrent connections)")
 	flag.IntVar(&duration, "d", 10, "Duration of test in seconds")
 	flag.IntVar(&timeoutms, "T", 1000, "Socket/request timeout in ms")
+	flag.IntVar(&cpus, "cpus", 0, "Number of cpus, i.e. GOMAXPROCS. 0 = system default.")
 	flag.StringVar(&method, "M", "GET", "HTTP method")
 	flag.StringVar(&host, "host", "", "Host Header")
 	flag.Var(&headerFlags, "H", "Header to add to each request (you can define multiple -H flags)")
@@ -69,9 +72,15 @@ func printDefaults() {
 	})
 }
 
+func mapToString(m map[string]int) string {
+	s := make([]string,0,len(m))
+	for k,v := range m {
+		s = append(s,fmt.Sprint(k,"=",v))
+	}
+	return strings.Join(s,",")
+}
+
 func main() {
-	//raising the limits. Some performance gains were achieved with the + goroutines (not a lot).
-	runtime.GOMAXPROCS(runtime.NumCPU() + goroutines)
 
 	statsAggregator = make(chan *loader.RequesterStats, goroutines)
 	sigChan := make(chan os.Signal, 1)
@@ -112,6 +121,10 @@ func main() {
 		return
 	}
 
+	if cpus > 0 {
+		runtime.GOMAXPROCS(cpus)
+	}
+
 	fmt.Printf("Running %vs test @ %v\n  %v goroutine(s) running concurrently\n", duration, testUrl, goroutines)
 
 	if len(reqBody) > 0 && reqBody[0] == '@' {
@@ -127,12 +140,14 @@ func main() {
 	loadGen := loader.NewLoadCfg(duration, goroutines, testUrl, reqBody, method, host, header, statsAggregator, timeoutms,
 		allowRedirectsFlag, disableCompression, disableKeepAlive, skipVerify, clientCert, clientKey, caCert, http2)
 
+	start := time.Now()
+
 	for i := 0; i < goroutines; i++ {
 		go loadGen.RunSingleLoadSession()
 	}
 
 	responders := 0
-	aggStats := loader.RequesterStats{MinRequestTime: time.Minute}
+	aggStats := loader.RequesterStats{ErrMap: make(map[string]int), Histogram: histo.New(1,int64(duration * 1000000),4)}
 
 	for responders < goroutines {
 		select {
@@ -144,25 +159,54 @@ func main() {
 			aggStats.NumRequests += stats.NumRequests
 			aggStats.TotRespSize += stats.TotRespSize
 			aggStats.TotDuration += stats.TotDuration
-			aggStats.MaxRequestTime = util.MaxDuration(aggStats.MaxRequestTime, stats.MaxRequestTime)
-			aggStats.MinRequestTime = util.MinDuration(aggStats.MinRequestTime, stats.MinRequestTime)
 			responders++
+			for k,v := range stats.ErrMap {
+				aggStats.ErrMap[k] += v
+			}
+			aggStats.Histogram.Merge(stats.Histogram)
 		}
 	}
 
+	duration := time.Now().Sub(start)
+
 	if aggStats.NumRequests == 0 {
-		fmt.Println("Error: No statistics collected / no requests found\n")
+		fmt.Println("Error: No statistics collected / no requests found")
+		fmt.Printf("Number of Errors:\t%v\n", aggStats.NumErrs)
+		if aggStats.NumErrs > 0 {
+			fmt.Printf("Error Counts:\t\t%v\n", mapToString(aggStats.ErrMap))
+		}
 		return
 	}
 
 	avgThreadDur := aggStats.TotDuration / time.Duration(responders) //need to average the aggregated duration
 
 	reqRate := float64(aggStats.NumRequests) / avgThreadDur.Seconds()
-	avgReqTime := aggStats.TotDuration / time.Duration(aggStats.NumRequests)
 	bytesRate := float64(aggStats.TotRespSize) / avgThreadDur.Seconds()
+
+	overallReqRate := float64(aggStats.NumRequests) / duration.Seconds()
+	overallBytesRate := float64(aggStats.TotRespSize) / duration.Seconds()
+
 	fmt.Printf("%v requests in %v, %v read\n", aggStats.NumRequests, avgThreadDur, util.ByteSize{float64(aggStats.TotRespSize)})
-	fmt.Printf("Requests/sec:\t\t%.2f\nTransfer/sec:\t\t%v\nAvg Req Time:\t\t%v\n", reqRate, util.ByteSize{bytesRate}, avgReqTime)
-	fmt.Printf("Fastest Request:\t%v\n", aggStats.MinRequestTime)
-	fmt.Printf("Slowest Request:\t%v\n", aggStats.MaxRequestTime)
+	fmt.Printf("Requests/sec:\t\t%.2f\nTransfer/sec:\t\t%v\n", reqRate, util.ByteSize{bytesRate})
+	fmt.Printf("Overall Requests/sec:\t%.2f\nOverall Transfer/sec:\t%v\n", overallReqRate, util.ByteSize{overallBytesRate})
+	fmt.Printf("Fastest Request:\t%v\n", toDuration(aggStats.Histogram.Min()))
+	fmt.Printf("Avg Req Time:\t\t%v\n", toDuration(int64(aggStats.Histogram.Mean())))
+	fmt.Printf("Slowest Request:\t%v\n", toDuration(aggStats.Histogram.Max()))
 	fmt.Printf("Number of Errors:\t%v\n", aggStats.NumErrs)
+	if aggStats.NumErrs > 0 {
+		fmt.Printf("Error Counts:\t\t%v\n", mapToString(aggStats.ErrMap))
+	}
+	fmt.Printf("10%%:\t\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.10)))
+	fmt.Printf("50%%:\t\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.50)))
+	fmt.Printf("75%%:\t\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.75)))
+	fmt.Printf("99%%:\t\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.99)))
+	fmt.Printf("99.9%%:\t\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.999)))
+	fmt.Printf("99.9999%%:\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.999999)))
+	fmt.Printf("99.99999%%:\t\t%v\n", toDuration(aggStats.Histogram.ValueAtPercentile(.9999999)))
+	fmt.Printf("stddev:\t\t\t%v\n", toDuration(int64(aggStats.Histogram.StdDev())))
+	// aggStats.Histogram.PercentilesPrint(os.Stdout,1,1)
+}
+
+func toDuration(usecs int64) time.Duration {
+	return time.Duration(usecs*1000)
 }

go.mod

@@ -2,6 +2,9 @@ module github.com/tsliwowicz/go-wrk
 
 go 1.21
 
-require golang.org/x/net v0.28.0
+require (
+	github.com/HdrHistogram/hdrhistogram-go v1.1.2
+	golang.org/x/net v0.28.0
+)
 
 require golang.org/x/text v0.17.0 // indirect

go.sum

@@ -1,4 +1,64 @@
+dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
+github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
+github.com/HdrHistogram/hdrhistogram-go v1.1.2 h1:5IcZpTvzydCQeHzK4Ef/D5rrSqwxob0t8PQPMybUNFM=
+github.com/HdrHistogram/hdrhistogram-go v1.1.2/go.mod h1:yDgFjdqOqDEKOvasDdhWNXYg9BVp4O+o5f6V/ehm6Oo=
+github.com/ajstarks/svgo v0.0.0-20180226025133-644b8db467af/go.mod h1:K08gAheRH3/J6wwsYMMT4xOr94bZjxIelGM0+d/wbFw=
+github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fogleman/gg v1.2.1-0.20190220221249-0403632d5b90/go.mod h1:R/bRT+9gY/C5z7JzPU0zXsXHKM4/ayA+zqcVNZzPa1k=
+github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
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 golang.org/x/net v0.28.0/go.mod h1:yqtgsTWOOnlGLG9GFRrK3++bGOUEkNBoHZc8MEDWPNg=
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 golang.org/x/text v0.17.0 h1:XtiM5bkSOt+ewxlOE/aE/AKEHibwj/6gvWMl9Rsh0Qc=
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+gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+rsc.io/pdf v0.1.1/go.mod h1:n8OzWcQ6Sp37PL01nO98y4iUCRdTGarVfzxY20ICaU4=

loader/loader.go

@@ -2,16 +2,17 @@ package loader
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"net/url"
 	"strings"
 	"sync/atomic"
 	"time"
 
+	histo "github.com/HdrHistogram/hdrhistogram-go"
 	"github.com/tsliwowicz/go-wrk/util"
 )
 
@@ -40,14 +41,14 @@ type LoadCfg struct {
 	http2              bool
 }
 
-// RequesterStats used for colelcting aggregate statistics
+// RequesterStats used for collecting aggregate statistics
 type RequesterStats struct {
 	TotRespSize    int64
 	TotDuration    time.Duration
-	MinRequestTime time.Duration
-	MaxRequestTime time.Duration
 	NumRequests    int
 	NumErrs        int
+	ErrMap		   map[string]int
+	Histogram	   *histo.Histogram
 }
 
 func NewLoadCfg(duration int, // seconds
@@ -103,7 +104,7 @@ func escapeUrlStr(in string) string {
 
 // DoRequest single request implementation. Returns the size of the response and its duration
 // On error - returns -1 on both
-func DoRequest(httpClient *http.Client, header map[string]string, method, host, loadUrl, reqBody string) (respSize int, duration time.Duration) {
+func DoRequest(httpClient *http.Client, header map[string]string, method, host, loadUrl, reqBody string) (respSize int, duration time.Duration, err error) {
 	respSize = -1
 	duration = -1
 
@@ -116,8 +117,7 @@ func DoRequest(httpClient *http.Client, header map[string]string, method, host,
 
 	req, err := http.NewRequest(method, loadUrl, buf)
 	if err != nil {
-		fmt.Println("An error occured doing request", err)
-		return
+		return 0,0,err
 	}
 
 	for hk, hv := range header {
@@ -131,28 +131,25 @@ func DoRequest(httpClient *http.Client, header map[string]string, method, host,
 	start := time.Now()
 	resp, err := httpClient.Do(req)
 	if err != nil {
-		fmt.Println("redirect?")
 		// this is a bit weird. When redirection is prevented, a url.Error is retuned. This creates an issue to distinguish
 		// between an invalid URL that was provided and and redirection error.
-		rr, ok := err.(*url.Error)
+		_, ok := err.(*url.Error)
 		if !ok {
-			fmt.Println("An error occured doing request", err, rr)
-			return
+			return 0,0,err
 		}
-		fmt.Println("An error occured doing request", err)
+		return 0,0,err
 	}
 	if resp == nil {
-		fmt.Println("empty response")
-		return
+		return 0,0,errors.New("empty response")
 	}
 	defer func() {
 		if resp != nil && resp.Body != nil {
 			resp.Body.Close()
 		}
 	}()
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
-		fmt.Println("An error occured reading body", err)
+		return 0,0,err
 	}
 	if resp.StatusCode/100 == 2 { // Treat all 2XX as successful
 		duration = time.Since(start)
@@ -161,16 +158,23 @@ func DoRequest(httpClient *http.Client, header map[string]string, method, host,
 		duration = time.Since(start)
 		respSize = int(resp.ContentLength) + int(util.EstimateHttpHeadersSize(resp.Header))
 	} else {
-		fmt.Println("received status code", resp.StatusCode, "from", resp.Header, "content", string(body), req)
+		return 0,0,errors.New(fmt.Sprint("received status code ", resp.StatusCode))
 	}
 
 	return
 }
 
+func unwrap(err error) error {
+	for errors.Unwrap(err)!=nil {
+		err = errors.Unwrap(err);
+	}
+	return err
+}
+
 // Requester a go function for repeatedly making requests and aggregating statistics as long as required
 // When it is done, it sends the results using the statsAggregator channel
 func (cfg *LoadCfg) RunSingleLoadSession() {
-	stats := &RequesterStats{MinRequestTime: time.Minute}
+	stats := &RequesterStats{ErrMap: make(map[string]int), Histogram: histo.New(1,int64(cfg.duration * 1000000),4)}
 	start := time.Now()
 
 	httpClient, err := client(cfg.disableCompression, cfg.disableKeepAlive, cfg.skipVerify,
@@ -180,12 +184,14 @@ func (cfg *LoadCfg) RunSingleLoadSession() {
 	}
 
 	for time.Since(start).Seconds() <= float64(cfg.duration) && atomic.LoadInt32(&cfg.interrupted) == 0 {
-		respSize, reqDur := DoRequest(httpClient, cfg.header, cfg.method, cfg.host, cfg.testUrl, cfg.reqBody)
-		if respSize > 0 {
+		respSize, reqDur, err := DoRequest(httpClient, cfg.header, cfg.method, cfg.host, cfg.testUrl, cfg.reqBody)
+		if err != nil {
+			stats.ErrMap[unwrap(err).Error()]+=1
+			stats.NumErrs++
+		} else if respSize > 0 {
 			stats.TotRespSize += int64(respSize)
 			stats.TotDuration += reqDur
-			stats.MaxRequestTime = util.MaxDuration(reqDur, stats.MaxRequestTime)
-			stats.MinRequestTime = util.MinDuration(reqDur, stats.MinRequestTime)
+			stats.Histogram.RecordValue(reqDur.Microseconds());
 			stats.NumRequests++
 		} else {
 			stats.NumErrs++