Strange GC behaviour

[aka.spin]

I recently tested the "helloworld" example of http package:

package main

import (
"http"
"io"
"log"
)

// hello world, the web server
func HelloServer(w http.ResponseWriter, req *http.Request) {
io.WriteString(w, "hello, world!\n")
}

func main() {
http.HandleFunc("/hello", HelloServer)
err := http.ListenAndServe(":8080", nil)
if err != nil {
log.Exit("ListenAndServe: ", err.String())
}
}

I run siege with file of 50000 different urls like "localhost:8080/1",
"localhost:8080/2" etc. All cool. But I see very confusing memory
usage:

- Just started - before testing: VIRT 10005, RES 2520
- After test: VIRT 31732, RES 24476

Half an hour later the value remained the same and did not decrease.
Is http caches any data?

[Ibrahim M. Ghazal]

On Oct 24, 5:11 pm, "aka.spin" <aka.s...@gmail.com> wrote:
> I run siege with file of 50000 different urls like "localhost:8080/1",
> "localhost:8080/2" etc. All cool. But I see very confusing memory
> usage:
>
>   - Just started - before testing: VIRT 10005, RES 2520
>   - After test: VIRT 31732, RES 24476
>
> Half an hour later the value remained the same and did not decrease.
> Is http caches any data?

As far as I know, the current garbage collector doesn't release memory
back to the operating system.

Similar questions has appeared many times on the mailing list. I think
it's worth adding to the FAQ.

[aka.spin]

Ok. Let's test:

package main

import (
"time"
"log"
)

type Big struct {
Data string
}

func biggy () {
a := &Big{}
a.Data = "Very very long string"
}

func main() {
log.Print("Prepare")
time.Sleep(10000000000)
log.Print("Trashing")
for i := 0; i<100000000; i++ {
biggy()
}
log.Print("All done")
for {
time.Sleep(1000000)
}
}

Results:

- Prepare phase: VIRT 7220, RES 940, SHR 504
- Trashing phase: VIRT 10108, RES 2216, SHR 924
- After all: VIRT 10108, RES 2216, SHR 924

Wow! It has not yet been added to the FAQ? Major developers, that with
you? Thank you all, I'm gone.

[Russ Cox]

> Thank you all, I'm gone.

Goodbye.

Russ