Re: [Caml-list] Re: memory usage

[Richard Jones <rich@annexia.org>]

On Mon, Jan 12, 2009 at 07:28:15PM +0800, John Lepikhin wrote:
> > To get real memory used, (Sys.word_size * live_word / 8). Do you use
> > out-of-heap datastructure that can use memory ? (malloc-ed
> > datastructure).
> 
> The only specific module is ocaml-fd (send file descriptors over pipes).

What version of OCaml is this?

I had a look at the source for ocaml-fd and it doesn't seem like it
should leak memory.  Certainly if there is a memory leak, it would be
a subtle one.

> I have suspicion on it, but as I said before, 90% of process memory is
> filled with specific text data, which is got inside threads and sent to
> socket using Unix.write. This data doesn't look like file
> descriptors :-)
> All other modules are from distribution (Unix, String, Mutex, Threads).

It does seem very unlikely that Unix.write would be a problem -- it's
a very commonly used function.

I'm afraid to say that you'll have to post a short reproducer here
before I can look at this further ...

> I heard about ocaml-memprof patch. Will it help here?

I haven't used it.  Seems like you have to patch the compiler.

If you suspect a problem in a C binding somewhere, then a quicker
approach would probably be to run the program using valgrind.

Rich.

-- 
Richard Jones
Red Hat