Write allocated mallocs

[Ben Israel]

I have noticed some unexpected behavior of my Linux 2.4.7 kernel. It appears
that my user level task is only allowed 512 mallocs before each malloc
starts getting physical memory. I want to malloc virtual address space and
only get physical memory when I write to a page. Is this some compiled
constant in the kernel? Are there any ways to get more? Where can I read
about such architecture decisions, so other behavior won't be so unexpected?

Ben Israel