Re: 64 bit program

On Thu, 24 Apr 2008 12:59:17 -0700, Karl E. Peterson wrote:

expvb wrote:
"Karl E. Peterson" <karl@xxxxxxxx> wrote ...
The bottleneck is the disk subsystem, so no. If I could use RAM for
spool, yeah, running parallel threads would be the very next optimization!

You could ask someone to modify one of the Ramdisk drivers samples, so you
can call it from VB6 by using DeviceIoControl to make it map 1 GB pages in
your process with the desired page from physical RAM, so the file management
overhead is removed. MSDN DDK(Now WDK) has samples for 32 bits and probably
64 bits Ramdisks. You could ask in the C++ group, or freelance sites to make
that driver for you, which simpler than a Ramdisk.

RAMDisk Sample(32 Bits):
http://msdn2.microsoft.com/en-us/library/aa490479.aspx

I think I'm missing how that might address the immediate situation, which is that I
lack a system with more than 4Gb of addressable RAM. And if I had such a system, I
could just use ordinary MMF techniques to access a(ny) RAM disk, right?

I'm probably missing something, but if you expect to physically run out of
RAM, won't the system experience the same disk I/O bottleneck you are
experiencing right now? How is a RAM drive going to speed anything up if
you do not have as much physical RAM as the ramdrive size. If I'm not
mistaken, won't Windows just page excess to the pagefile?

The OP states he would like to develop for 64 bit windows, and if he wants
to address more than 16GB of RAM he'll need 64 bit Vista. But, in the end
if the system doesn't have enough installed RAM, the disk subsystem will
still be the bottleneck, right?

Ultimately this is just to satisfy my own curiosity as it seems you are far
more knowledgable in this than I am.

--
HK
.

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