Re: Memory Leakage

[Havoc Pennington <hp redhat com>]

Matthew Russell <twig5151 yahoo com> writes:
> I'm having a problem with leaking memory from a
> dialog box. It contains a notebook with 4 pages,
> one of which just contains a few labels and
> buttons, whereas the others contain fairly large
> sized Clist. When I come to destroy the window,
> it seems to leak about 100k, according to top.
> (This is based on creating and destroying several
> of these dialogs in sequence.)

Top's memory usage does not mean much about whether you have leaked
memory. top reports memory given to the process via brk(). The C
library malloc() implementation, and also lots of the stuff in GLib,
will cache memory from brk() even though the app has freed it, because
brk() is a system call and therefore sort of expensive. Also, memory
fragmentation can force malloc to keep memory chunks from brk() even
though they aren't fully used.

To catch mem leaks, use a tool such as memprof, and be very sure what
the memory management rules are for the API you're using.

Havoc