>The guess here is that Linux' internal AVLtree mechanism for
>representing process address space is more graceful at handling a very
>very lange numbers of allocations and deallocations of very small VM
>regions (e.g., maybe only one page?) than the rather simple
>linked-list code in NetBSD.

But the thing that I don't understand is why Applixware is the only X
application in the universe that evokes this behavior.

Anyway, the thing that I thought would be easier would be to write up
a small test program that demonstrated the problem just by using the XFree
InternalMalloc, rather than profiling the entire X server (eliminate
random noise).  Then you could start profiling the kernel.

--Ken