I would suggest that since the time required to do the context switching to
change memory maps for different processes is not significant and since
Windows Vista is designed to be used on Personnel Computers by one user at a
time that it would have made no sense to provide for multithreaded
applications that could use multiple processes and memory mapping as is a
requirement in a server environment that has hundreds of users logged on
concurrently.
"Colin Barnhorst" wrote in message
news
What keeps getting missed is the reason why a functionality to extend past
the 4GB limit is not available to Windows clients like XP so that us
technology enthusiasts can romp and play in Big Memory Land.

Dennis is saying it could be done and that is true. He is saying
therefore MS chose not to enable it in Windows clients and faults them for
not doing so. That's where I disagree. My take on that point is that MS
concluded that PAE is not the solution they wanted to present to Windows
client users because moving on to 64bit Windows clients was the more
robust solution by far.

There isn't much beyond this point that is getting anywhere in this
thread. The technical woulda, coulda, shoulda stuff really misses the
point of why MS didn't bother to use PAE to address the 4GB limitations in
32bit Windows clients.

Providing 64bit operating systems is a far better resolution of the issue
than a workaround for 32bit. For that I applaud MS, not fault them.

"Charlie Tame" wrote in message
...
Yes Dennis was correct but so is the 4GB limit if some other technology
is not used. My point was that if "Something else" is not used then the
original statement that there is a 4GB limit was correct.

Curious wrote:
As Colin pointed out in one of his posts yes you can support more the
4GB of physical memory with a 32bit OS if you provide different
threads/users each with their own individual logical memory map which is
limited to no more the 4GB. 32 bit Server Operating systems have used
this technique for years to support large large numbers of users on
large memory systems. Also by providing separate logical memory maps
for different users servers are able to insure that the programs or data
being used by one user can not be corrupted by another server user.
Dennis is correct when he states that with a 32 bit OS that supports
memory mapping one can develop an application that use more then 4GB of
physical memory by spreading the functionality across multiple processes
each of which is limited to its own 4GB of logical address space.

"dennis" wrote in message
...
Charlie Tame wrote:

But I could NOT use BASIC routines and the underlying RAM at the same
time.

Try and count the number of address pins on a 32-bit CPU that supports
36bit PAE, and tell me if anything needs to overlap



Yes he