Re: 32-bit programs on Windows x64

There is no way to discover this. There are so many processes running that if you really
need 4GB of physical memory available to hold your entire process, you will need at least
an 8GB machine, AND EVEN THEN THERE IS NO GUARANTEE THAT PAGING WILL NOT OCCUR. It is
essentially not under your control. You can try ::VirtualLock, but it doesn't guarantee
that you can lock things down (and you need special admin configuration parameters to
allow it to work at all, and you have to set your working set quota).

Any belief that Windows can sustain real-time behavior is based on various delusional
systems. It is not real-time and any illusion that it is real-time is just that, an
illusion.

A swapping operation takes 10-50ms depending on a variety of parameters. But it is
impossible to process 4.2GB of data in 1/10 of a second using ANY algorithm, even if there
is nothing going on. Therefore the only thing that matters is the actual working set.

Perhaps you really have an infeasible project.
joe


On Thu, 3 Jul 2008 14:03:01 -0700 (PDT), PeteOlcott <PeteOlcott@xxxxxxxxx> wrote:

What part of "virtual memory is not physical memory" are you missing.  I've said this
eight or ten or a dozen times, VIRTUAL MEMORY IS NOT PHYSICAL MEMORY.  

Not only does my process require 4.0 GB of RAM, it is also time
critical. If there is any swapping to and from VM, then the current
project becomes infeasible. I must know how much actual RAM is
available to my process, even though this actual RAM will be mapped to
VM. If three is any swapping to and from disk, the current project
becomes infeasible, my maximum response time is 1/10 second.
Joseph M. Newcomer [MVP]
email: newcomer@xxxxxxxxxxxx
Web: http://www.flounder.com
MVP Tips: http://www.flounder.com/mvp_tips.htm
.

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