memory usage

[Samuel Thibault <samuel.thibault@ens-lyon.org>]

I've ported xosview to GNU/Hurd and had a look during a gcc compilation:
approximately only half the memory is used.  I had a look at
vm/vm_pageout.c and noticed:

/*      When vm_page_external_count exceeds vm_page_external_limit, 
 *      allocations of externally paged pages stops.
 */

#ifndef VM_PAGE_EXTERNAL_LIMIT
#define VM_PAGE_EXTERNAL_LIMIT(free)            ((free) / 2)
#endif  /* VM_PAGE_EXTERNAL_LIMIT */

Does Mach really need half the memory just for itself? I'd say most
memory is for user space: libraries, pictures, ... This limit probably
needs tuning (or even disabled), at least in Debian.

Samuel