Re: [Valgrind-users] Client requests for comparitive heap measurement

[Howard C. <hy...@sy...>]

Ashley Pittman wrote:
> On Thu, 2006-01-26 at 07:26 +0100, Oswald Buddenhagen wrote:
>   
>> On Wed, Jan 25, 2006 at 06:36:19PM -0800, Graydon Hoare wrote:
>>     
>>> I'm working on characterizing mozilla's memory use, in order to 
>>> eventually make it use less. I am hoping to use valgrind for this.
>>>
>>>       
>> ok, maybe i'm totally wrong, but i would not use valgrind for this. 
>> as you want to do allocation and leak tracking only, you don't need any
>> instrumentation except wrapping the allocator functions (which, i guess,
>> the nspr(?) does anyway) and doing a snapshot each time you need it
>> (memcheck does the same, afaik). that would mean that integrating a
>> *way* more lightweight "classical" memory debugger library would be more
>> appropriate. depends on what else you want to track at the same time ...
>>     
>
> Sorry if this is too off-topic for this list...
>
> I've done exactly this to track memory leaks in programs, it's actually
> quite easy once you know how.
>
> There are hooks inside libc (man 3 malloc_hook) you can use to intercept
> every malloc/calloc/memalign/free call from everywhere in the
> application/library's it's using (you don't even need the source to do
> this).  These callbacks are given the size and base of the buffer but
> also the return address for the function that called malloc() in the
> first place.
>   

Those hooks only exist for glibc. My FunctionCheck code shows how to 
intercept malloc/etc. for any libdl-based dynamic library platform (e.g. 
Solaris, Irix, Linux, etc...)

http://www.highlandsun.com/hyc/#fncchk

-- 
  -- Howard Chu
  Chief Architect, Symas Corp.  http://www.symas.com
  Director, Highland Sun        http://highlandsun.com/hyc
  OpenLDAP Core Team            http://www.openldap.org/project/