On Tue, Feb 10, 1998 at 04:00:51PM +0100, Matthieu Herrb wrote:
>  > Why does the internal malloc of XFree make the list grow to 157 entries in
>  > one day when the other allocation method behaves a lot better?  
> 
> Because the XFree86 internal allocator uses mmap(/dev/zero) instead of sbrk()
> to get memory from the system, in order to be able to release
> arbitrary chunks when they are freezed...

Hmm.. but shouldn't the entries be removed from the list whenever chunks of
memory are released?

>  > And why do
>  > things become so slow when the list length grows to 150+ entries?
> 
> Good question. Nobody knows if other OS don't see the problem because
> no one runs applix on them or if they are more efficient in handling
> lots of mmap() calls.

I'm sure lots of people are running Applix on linux and not seeing the
problem.  Even the XFree folks didn't know about the problem when I talked
to them.  I'm pretty sure this is a NetBSD specific thing.. which only
pops up with programs like Applix which send lots and lots of small requests
to the X server.

The linux acroreader may have the same problem.  I haven't ktraced it,
but it sure runs slow on my P166 when compared to BSDI Netscape, for
example.

  -jm