Re: [Caml-list] Finding memory leakage using Gc module

[ygrek <ygrekheretix@gmail.com>]

On Wed, 1 Jun 2011 14:40:06 +0200
Hans Ole Rafaelsen <hrafaelsen@gmail.com> wrote:

> Hi,
> 
> is there some way to monitor memory being allocated (and still in use) when
> calling a function? In the first case below it should report close to 0 and
> in the second close to 10240. But here it reports 10368 in both cases.
> Gc.allocated_bytes seems to report allocated bytes without reporting what it
> was able to free. Have also tried other Gc functions such as Gc.counters. Is
> it some way to find out which bytes have been allocated and not freed after
> calling a function? Is there some good methods that people use to find out
> (get a hint of) which memory is leaking?

Using full_major (to empty minor heap) and looking at live_words works :

open Gc

let str = ref ""

let f () =
        full_major ();
        let before = (stat ()).live_words in
        str := String.create 102400;
        str := "";
        Gc.full_major ();
        let after = (stat ()).live_words in
        let delta = after - before in
        Printf.printf "Words used: %d\n%!" delta

let g () =
        Gc.full_major ();
        let before = (stat ()).live_words in
        str := String.create 102400;
        Gc.full_major ();
        let after = (stat ()).live_words in
        let delta = after - before in
        Printf.printf "Words used: %d\n%!" delta

-- 
 ygrek
 http://ygrek.org.ua