@chapter Paging I/O

Raw paging involves low-level address translation on the Mac side;
a fairly complex scheme may be required to simultaneously

@itemize @bullet
@item minimize LISP software changes;
@item support required K changes; and
@item fit comfortably within the robust Macintosh environment.
@end(itemize)

The Mac application will assume the burden of maintaining address maps
below the LISP view of physical addresses.  Everything else will be
done in LISP and must be compatible with current code.

If Size(Minimum_Pageable_Unit)  Size(disk block), then look up the
physical addresses of the paging files and eliminate all chunks which
are not contiguous in physical memory. The paging files must always be
kept open by the application.

We may want to use Mac memory as a paging disk cache.  Can the Mac's
cache be used to build such a thing? Or must we start from scratch?

"We probably cannot improve performance with a paging
cache smaller than main memory."		--rwk

The LISP Machine does virtual ---> physical address translation, which
the Mac then translates into (native) physical disk (locations).
These addresses are derived from files, not partitions as previously
suggested.

@textbox
@center Montreal notes:

Scheme is:
Read in, put at physical address, start copying.
Command to find out how much paging space there is.

@end textbox