pprof not working

gistfile1.txt

package main

import (
	"github.com/samuell/blow"
	"github.com/trustmaster/goflow"
	"runtime"
    "runtime/pprof"
    "flag"
    "os"
    "log"
)

const (
	NUMTHREADS = 4
)

// ---------------------------------------------------------
// BaseComplementer network
// ---------------------------------------------------------
type BaseComplementerApp struct {
	flow.Graph
}

func NewBaseCompelenterApp() *BaseComplementerApp {
	network := new(BaseComplementerApp)
	network.InitGraphState()

	// Add components
	network.Add(new(blow.FileReader), "filereader")
	network.Add(new(blow.BaseComplementer), "bc1")
	network.Add(new(blow.BaseComplementer), "bc2")
	network.Add(new(blow.BaseComplementer), "bc3")
	network.Add(new(blow.BaseComplementer), "bc4")
	network.Add(new(blow.Printer), "printer")

	// Connect components
	network.MapInPort("In", "filereader", "FileName")
	network.Connect("filereader", "Line", "bc1", "Sequence", make(chan []byte))
	network.Connect("bc1", "BaseComplementedSequence", "bc2", "Sequence", make(chan []byte))
	network.Connect("bc2", "BaseComplementedSequence", "bc3", "Sequence", make(chan []byte))
	network.Connect("bc3", "BaseComplementedSequence", "bc4", "Sequence", make(chan []byte))
	network.Connect("bc4", "BaseComplementedSequence", "printer", "Line", make(chan []byte))

	return network
}

// ---------------------------------------------------------
// Main method
// ---------------------------------------------------------
var finish chan bool

// Use this handler to let main() know when the network terminates
func (a *BaseComplementerApp) Finish() {
	finish <- true
}

// Profiling stuff ... from http://blog.golang.org/profiling-go-programs
var cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")

func main() {
    flag.Parse()
    if *cpuprofile != "" {
        f, err := os.Create(*cpuprofile)
        if err != nil {
            log.Fatal(err)
        }
        pprof.StartCPUProfile(f)
        defer pprof.StopCPUProfile()
    }        
    
	// Set the number of Operating System-threads to use
	runtime.GOMAXPROCS(NUMTHREADS)

	// Termination signal channel
	finish = make(chan bool)
	// Create network
	net := NewBaseCompelenterApp()

	// Create the "In" channel
	in := make(chan string)
	net.SetInPort("In", in)

	// Run net
	flow.RunNet(net)

	// Give the Filename to read
	in <- "Homo_sapiens.GRCh37.67.dna_rm.chromosome.Y.fa"

	close(in)
	<-finish
}

Works now, when putting pprof.StopCPUProfile() at end of main(), without defer ... like so:

func main() {
    flag.Parse()
    if *cpuprofile != "" {
        f, err := os.Create(*cpuprofile)
        if err != nil {
            fmt.Println("Error: ", err)
        }
        cpuerr := pprof.StartCPUProfile(f)
        if cpuerr != nil {
            fmt.Println("Start CPU Profile error: ", cpuerr)
        }
    }

    // Set the number of Operating System-threads to use
    runtime.GOMAXPROCS(NUMTHREADS)

    // Termination signal channel
    finish = make(chan bool)
    // Create network
    net := NewBaseCompelenterApp()

    // Create the "In" channel
    in := make(chan string)
    net.SetInPort("In", in)

    // Run net
    flow.RunNet(net)

    // Give the Filename to read
    in <- "Homo_sapiens.GRCh37.67.dna_rm.chromosome.Y.fa"

    close(in)
    <-finish
    pprof.StopCPUProfile()
}