2
\$\begingroup\$

I wanted to test the performance of concurrent http request in Go against node.js:

package main

import (
  "fmt"
  "time"
  "strconv"
  "net/http"
)

var responseCounter = 0
var requestCounter = 0
var count=0
var ch = make(chan int)

func sendRequest(){
    go func() {
        requestCounter++
        url := "https://www.google.co.in/#q=search_" +strconv.Itoa(requestCounter)
        resp, err := http.Get(url)
        if err != nil {
            fmt.Printf("\nError",err)
        }
        defer resp.Body.Close()
        count++
        ch <- count
        sendRequest()
    }()
}

func main() {

    for i := 1; i<100; i++{
        sendRequest()
    }

    for {
        select {
            case r := <-ch:
                fmt.Printf("\nChannel ",r)
            case <-time.After(50 * time.Millisecond):
                //sendRequest()
        }
    }
}

When I run this code the CPU usage goes very high (around 90%). Is there something wrong with this code? Have I used the Goroutines correctly?

\$\endgroup\$
4
  • \$\begingroup\$ but you start infinitely many goroutines in your sendRequest, no? \$\endgroup\$
    – akonsu
    Commented Jan 9, 2015 at 16:29
  • \$\begingroup\$ I did so because I wanted the requests to be continuous. So when one http request is complete I made another request by calling sendRequest(). Is there a better way to achieve this? \$\endgroup\$
    – Sarita
    Commented Jan 10, 2015 at 15:52
  • \$\begingroup\$ try to wait for the goroutine to finish and then start another one. I do not know what is going on... \$\endgroup\$
    – akonsu
    Commented Jan 10, 2015 at 16:19
  • \$\begingroup\$ So many data races!! (go {build,install,run,test} -race is your friend). \$\endgroup\$
    – Dave C
    Commented Apr 12, 2015 at 17:00

1 Answer 1

7
\$\begingroup\$

Inside SendRequst you are calling SendRequest again, which will make your stack full of recursive calls.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.