ethr.go

//-----------------------------------------------------------------------------
// Copyright (C) Microsoft. All rights reserved.
// Licensed under the MIT license.
// See LICENSE.txt file in the project root for full license information.
//-----------------------------------------------------------------------------
package main

import (
	"flag"
	"fmt"
	"os"
	"runtime"
	"strings"
	"time"
)

const defaultLogFileName = "./ethrs.log for server, ./ethrc.log for client"
var gVersion string

func printFlagUsage(flag, info string, helptext ...string) {
	fmt.Printf("\t-%s %s\n", flag, info)
	for _, help := range helptext {
		fmt.Printf("\t\t%s\n", help)
	}
}

func printServerUsage() {
	printFlagUsage("s", "", "Run in server mode.")
}

func printClientUsage() {
	printFlagUsage("c", "<server>", "Run in client mode and connect to <server>.",
		"Server is specified using name, FQDN or IP address.")
}

func printExtClientUsage() {
	printFlagUsage("c", "<destination>", "Run in external client mode and connect to <destination>.",
		"<destination> is specified using host:port format.",
		"Example: www.microsoft.com:443 or 10.1.0.4:22 etc.")
}

func printPortUsage() {
	printFlagUsage("ports", "<k=v,...>", "Use custom port numbers instead of default ones.",
		"A comma separated list of key=value pair is used.",
		"Key specifies the protocol, and value specifies base port.",
		"Ports used for various tests are calculated from base port.",
		"Example: For TCP, Bw: 9999, CPS: 9998, PPS: 9997, Latency: 9996",
		"Control is used for control channel communication for ethr.",
		"Note: Same configuration must be used on both client & server.",
		"Default: 'control=8888,tcp=9999,udp=9999,http=9899,https=9799'")
}

func printExtPortUsage() {
	printFlagUsage("ports", "<k=v,...>", "Use custom port numbers instead of default ones.",
		"A comma separated list of key=value pair is used.",
		"Key specifies the protocol, and value specifies the port.",
		"Default: 'tcp=9999,http=9899,https=9799'")
}

func printTestType() {
	printFlagUsage("t", "<test>", "Test to run (\"b\", \"c\", \"p\", or \"l\")",
		"b: Bandwidth",
		"c: Connections/s or Requests/s",
		"p: Packets/s",
		"l: Latency, Loss & Jitter",
		"Default: b - Bandwidth measurement.")
}

func printExtTestType() {
	printFlagUsage("t", "<test>", "Test to run (\"b\", \"c\", or \"cl\")",
		"b: Bandwidth",
		"c: Connections/s or Requests/s",
		"cl: TCP connection setup latency",
		"Default: b - Bandwidth measurement.")
}

func printThreadUsage() {
	printFlagUsage("n", "<number>", "Number of Parallel Sessions (and Threads).",
		"0: Equal to number of CPUs",
		"Default: 1")
}

func printDurationUsage() {
	printFlagUsage("d", "<duration>",
		"Duration for the test (format: <num>[ms | s | m | h]",
		"0: Run forever",
		"Default: 10s")
}

func printGapUsage() {
	printFlagUsage("g", "<gap>",
		"Time interval between successive measurements (format: <num>[ms | s | m | h]",
		"0: No gap",
		"Default: 1s")
}

func printBufLenUsage() {
	printFlagUsage("l", "<length>",
		"Length of buffer to use (format: <num>[KB | MB | GB])",
		"Only valid for Bandwidth tests. Max 1GB.",
		"Default: 16KB")
}

func printProtocolUsage() {
	printFlagUsage("p", "<protocol>",
		"Protocol (\"tcp\", \"udp\", \"http\", \"https\", or \"icmp\")",
		"Default: tcp")
}

func printExtProtocolUsage() {
	printFlagUsage("p", "<protocol>",
		"Protocol (\"tcp\", \"http\", \"https\", or \"icmp\")",
		"Default: tcp")
}

func printIterationUsage() {
	printFlagUsage("i", "<iterations>",
		"Number of round trip iterations for each latency measurement.",
		"Default: 1000")
}

func printModeUsage() {
	printFlagUsage("m", "<mode>",
		"'-m x' MUST be specified for external mode.")
}

func printNoConnStatUsage() {
	printFlagUsage("ncs", "",
		"No Connection Stats would be printed if this flag is specified.",
		"This is useful for running with large number of connections as",
		"specified by -n option.")
}

func ethrUsage() {
	fmt.Println("\nEthr - A comprehensive network performance measurement tool.")
    fmt.Println("Version: " + gVersion)
	fmt.Println("It supports 4 modes. Usage of each mode is described below:")

	fmt.Println("\nCommon Parameters")
	fmt.Println("================================================================================")
	printFlagUsage("h", "", "Help")
	printFlagUsage("no", "", "Disable logging to file. Logging to file is enabled by default.")
	printFlagUsage("o", "<filename>", "Name of log file. By default, following file names are used:",
		"Server mode: 'ethrs.log'",
		"Client mode: 'ethrc.log'",
		"External server mode: 'ethrxs.log'",
		"External client mode: 'ethrxc.log'")
	printFlagUsage("debug", "", "Enable debug information in logging output.")
	printFlagUsage("4", "", "Use only IP v4 version")
	printFlagUsage("6", "", "Use only IP v6 version")

	fmt.Println("\nMode: Server")
	fmt.Println("================================================================================")
	printServerUsage()
	printFlagUsage("ui", "", "Show output in text UI.")
	printPortUsage()

	fmt.Println("\nMode: Client")
	fmt.Println("================================================================================")
	printClientUsage()
	printFlagUsage("r", "", "For Bandwidth tests, send data from server to client.")
	printDurationUsage()
	printThreadUsage()
	printNoConnStatUsage()
	printBufLenUsage()
	printProtocolUsage()
	printPortUsage()
	printTestType()
	printIterationUsage()

	fmt.Println("\nMode: External Server")
	fmt.Println("================================================================================")
	printModeUsage()
	printServerUsage()
	printExtPortUsage()

	fmt.Println("\nMode: External Client")
	fmt.Println("================================================================================")
	printModeUsage()
	printExtClientUsage()
	printDurationUsage()
	printThreadUsage()
	printNoConnStatUsage()
	printBufLenUsage()
	printExtProtocolUsage()
	printExtTestType()
	printGapUsage()
}

func main() {
    //
    // If version is not set via ldflags, then default to UNKNOWN
    //
    if gVersion == "" {
        gVersion = "[VERSION: UNKNOWN]"
    }
	//
	// Set GOMAXPROCS to 1024 as running large number of goroutines in a loop
	// to send network traffic results in timer starvation, as well as unfair
	// processing time across goroutines resulting in starvation of many TCP
	// connections. Using a higher number of threads via GOMAXPROCS solves this
	// problem.
	//
	runtime.GOMAXPROCS(1024)

	flag.Usage = ethrUsage
	isServer := flag.Bool("s", false, "")
	clientDest := flag.String("c", "", "")
	testTypePtr := flag.String("t", "", "")
	thCount := flag.Int("n", 1, "")
	bufLenStr := flag.String("l", "16KB", "")
	protocol := flag.String("p", "tcp", "")
	outputFile := flag.String("o", defaultLogFileName, "")
	debug := flag.Bool("debug", false, "")
	noOutput := flag.Bool("no", false, "")
	duration := flag.Duration("d", 10*time.Second, "")
	showUI := flag.Bool("ui", false, "")
	rttCount := flag.Int("i", 1000, "")
	portStr := flag.String("ports", "", "")
	modeStr := flag.String("m", "", "")
	use4 := flag.Bool("4", false, "")
	use6 := flag.Bool("6", false, "")
	gap := flag.Duration("g", 0, "")
	reverse := flag.Bool("r", false, "")
	ncs := flag.Bool("ncs", false, "")

	flag.Parse()

	//
	// TODO: Handle the case if there are incorrect arguments
	// fmt.Println("Number of incorrect arguments: " + strconv.Itoa(flag.NArg()))
	//

	//
	// Only used in client mode, to control whether to display per connection
	// statistics or not.
	//
	noConnectionStats = *ncs

	xMode := false
	switch *modeStr {
	case "":
	case "x":
		xMode = true
	default:
		printUsageError("Invalid value for execution mode (-m).")
	}
	mode := ethrModeInv

	if *isServer {
		if *clientDest != "" {
			printUsageError("Invalid arguments, \"-c\" cannot be used with \"-s\".")
		}
		if xMode {
			mode = ethrModeExtServer
		} else {
			mode = ethrModeServer
		}
	} else if *clientDest != "" {
		if xMode {
			mode = ethrModeExtClient
		} else {
			mode = ethrModeClient
		}
	} else {
		printUsageError("Invalid arguments, use either \"-s\" or \"-c\".")
	}

	if *reverse && mode != ethrModeClient {
		printUsageError("Invalid arguments, \"-r\" can only be used in client mode.")
	}

	if *use4 && !*use6 {
		ipVer = ethrIPv4
	} else if *use6 && !*use4 {
		ipVer = ethrIPv6
	}

	bufLen := unitToNumber(*bufLenStr)
	if bufLen == 0 {
		printUsageError(fmt.Sprintf("Invalid length specified: %s" + *bufLenStr))
	}

	if *rttCount <= 0 {
		printUsageError(fmt.Sprintf("Invalid RTT count for latency test: %d", *rttCount))
	}

	var testType EthrTestType
	switch *testTypePtr {
	case "":
		switch mode {
		case ethrModeServer:
			testType = All
		case ethrModeExtServer:
			testType = All
		case ethrModeClient:
			testType = Bandwidth
		case ethrModeExtClient:
			testType = Bandwidth
		}
	case "b":
		testType = Bandwidth
	case "c":
		testType = Cps
	case "p":
		testType = Pps
	case "l":
		testType = Latency
	case "cl":
		testType = ConnLatency
	default:
		printUsageError(fmt.Sprintf("Invalid value \"%s\" specified for parameter \"-t\".\n"+
			"Valid parameters and values are:\n", *testTypePtr))
	}

	p := strings.ToUpper(*protocol)
	proto := TCP
	switch p {
	case "TCP":
		proto = TCP
	case "UDP":
		proto = UDP
	case "HTTP":
		proto = HTTP
	case "HTTPS":
		proto = HTTPS
	case "ICMP":
		proto = ICMP
	default:
		printUsageError(fmt.Sprintf("Invalid value \"%s\" specified for parameter \"-p\".\n"+
			"Valid parameters and values are:\n", *protocol))
	}

	if *thCount <= 0 {
		*thCount = runtime.NumCPU()
	}

	//
	// For Pkt/s, we always override the buffer size to be just 1 byte.
	// TODO: Evaluate in future, if we need to support > 1 byte packets for
	//       Pkt/s testing.
	//
	if testType == Pps {
		bufLen = 1
	}

	testParam := EthrTestParam{EthrTestID{EthrProtocol(proto), testType},
		uint32(*thCount),
		uint32(bufLen),
		uint32(*rttCount),
		*reverse}
	validateTestParam(mode, testParam)

	generatePortNumbers(*portStr)

	logFileName := *outputFile
	if !*noOutput {
		if logFileName == defaultLogFileName {
			switch mode {
			case ethrModeServer:
				logFileName = "ethrs.log"
			case ethrModeExtServer:
				logFileName = "ethrxs.log"
			case ethrModeClient:
				logFileName = "ethrc.log"
			case ethrModeExtClient:
				logFileName = "ethrxc.log"
			}
		}
		logInit(logFileName, *debug)
	}

	clientParam := ethrClientParam{*duration, *gap}
	serverParam := ethrServerParam{*showUI}

	switch mode {
	case ethrModeServer:
		runServer(testParam, serverParam)
	case ethrModeExtServer:
		runXServer(testParam, serverParam)
	case ethrModeClient:
		runClient(testParam, clientParam, *clientDest)
	case ethrModeExtClient:
		runXClient(testParam, clientParam, *clientDest)
	}
}

func emitUnsupportedTest(testParam EthrTestParam) {
	printUsageError(fmt.Sprintf("\"%s\" test for \"%s\" is not supported.\n",
		testToString(testParam.TestID.Type), protoToString(testParam.TestID.Protocol)))
}

func validateTestParam(mode ethrMode, testParam EthrTestParam) {
	testType := testParam.TestID.Type
	protocol := testParam.TestID.Protocol
	if mode == ethrModeServer {
		if testType != All || protocol != TCP {
			emitUnsupportedTest(testParam)
		}
	} else if mode == ethrModeClient {
		switch protocol {
		case TCP:
			if testType != Bandwidth && testType != Cps && testType != Latency {
				emitUnsupportedTest(testParam)
			}
		case UDP:
			if testType != Bandwidth && testType != Pps {
				emitUnsupportedTest(testParam)
			}
			if testType == Bandwidth {
				if testParam.BufferSize > (64 * 1024) {
					printUsageError("Maximum supported buffer size for UDP is 64K\n")
				}
			}
		case HTTP:
			if testType != Bandwidth {
				emitUnsupportedTest(testParam)
			}
		case HTTPS:
			if testType != Bandwidth {
				emitUnsupportedTest(testParam)
			}
		default:
			emitUnsupportedTest(testParam)
		}
	} else if mode == ethrModeExtClient {
		if (protocol != TCP) || (testType != ConnLatency && testType != Bandwidth) {
			emitUnsupportedTest(testParam)
		}
	}
}

func printUsageError(s string) {
	fmt.Printf("Error: %s\n", s)
	fmt.Printf("Please use \"ethr -h\" for ethr command line arguments.\n")
	// ethrUsage()
	os.Exit(1)
}