malloc vs ptmalloc2

[Jason Henson]

On 02/13/05 03:21:29, David Schultz wrote:
> On Sun, Feb 13, 2005, Jason Henson wrote:
> > I saw on a few of the lists here how linux uses ptmalloc2 and it
> > outperforms bsd's malloc.  I tried to do some research into it and
> > found PHK's pdf on it and it seems bsd's malloc was ment to be ok  
> in
> 
> > most every situation. Because of this it shines when primary  
> storage
> is
> > seriously over committed.
> >
> > So here is my question, I use FreeBSD as a desktop and never ever
> use
> > swap(I just don't stress my system enough?), can I use ptmalloc in
> > stead of malloc?  Like defining SCHED_ULE instead of SCHED_4BSD.
> Can
> > the system malloc be switched out?
> 
> With a little bit of work, you should be able to replace
> src/lib/libc/stdlib/malloc.c.  ptmalloc is much more heavyweight,
> but it would probably do better in cases where you have a large
> number of threads doing a massive number of malloc/free operations
> on a multiprocessor system.  Other than that, I don't know enough
> details about ptmalloc to speculate, except to say that for most
> real-world workloads on modern systems, the impact of the malloc
> implementation is likely to be negligible.  Of course, test
> results would be interesting...

I see what you mean by heavy weight!  Looking through the sources.  The  
gains looked promising in this thread
http://docs.freebsd.org/cgi/mid.cgi?420BB1FF.11156.68F6CEC

I might find the time for it, and if I do I hope it is not too  
difficult.