[Arny Krueger]

"Scott Dorsey" wrote in message
...
Laurence Payne NOSPAMlpayne1ATdsl.pipex.com wrote:

Sure. As much AS POSSIBLE. Are you suggesting PT or Windows affords
data caching the same priority as it gives program code?

It's not data caching. It's virtual memory. It's done by Windows, and
the application has no control over it.

That
whenever a program accesses a data file larger than available RAM,
core will be swapped to disk in the interests of caching every last
possible byte of data? I think not :-)

No, you have it backwards. The program has a large address space that is
available for it to use. It is larger than the physical core space on
the computer. When a program goes to access memory that is not currently
swapped in, it swaps a page out to the page file, and swaps in one that
contains the memory block the application wants. In this way, the program
sees a very large address space without the computer actually needing to
have so much space in core.

Are you maybe falling into the common trap of thinking Virtual Memory
= paging file?

The paging file PLUS the physical memory IS the virtual memory space
available. This is early-1970s technology we are talking about here.

The virtual memory space available can easily exceed the sum of physical
memory and the paging file. Just because there is address space that is in
some sense available doesn't mean that it has to be backed up with physical
memory.