Today Tim Slattery commented courteously on the subject at
hand
You're confusing physical RAM with the virtual memory space
made available to processes.
I'm not confusing anything, Tim. A mobo, and Windoze, can
handle 4 gig of memory. It is phyiscal as it is installed, it
only becomes one of many forms of virtual memory as Windoze
bastardizes it's inefficient memory handling. My point was and
is that of the 4, Windoze hijacks/steals/"reserves" the top
gig for purpose or purposes unknow. I really don't want to
debate these nuances as they're irrelevant to most people, who
only want to know how many memory sticks their mobo can hold
and Windoze can address.
WinXP can handle 4GB of physical RAM.
Each process running in WinXP gets a 4GB virtual memory
space. The top 2GB of that space is reserved for the
operating system (the OS is mapped there, and will
appropriate working space for itself in that address
range). If you have exceptionally greedy applications, you
can use the /3GB switch in the boot.ini file. That will
make the OS use only the top 1GB.
If you want to believe that each process, or each account, can
have a full 4 gig, then please be my guest. In reality, you
can overload Windoze pitiful memory management with just 2 or
3 user accounts simultaneously running, particularly if they
are doing memory intensive tasks in the background, and the
user(s) are switching between one and another. One scenario is
2 or 3 physical users in the same room who want to launch off
a bunch of background tasks then yield keyboard/mouse time to
the next user and so one. Even with 4 gig, Windoze fairly
quickly gets tangled in its underwear and starts throwing
those neat little yellow upside down triangles with an
explamantion point in them yelling "system memory running
low".
But, to keep this out of some elitist theoretical discussion
and keep it real world, ordinary people only want to know how
much they can load down their system before it simultaneously
becomes CPU bound, HD bound, and memory constrainted (e.g. for
swap files or graphics app undo files). Once "real" memory
runs out, the HD will start thrashing.
Right now on my AMD 3700 4 gig Win XP Pro SP2 system, the only
thing going on is a background task copying 20-30 gig from my
D to an external HD. Of 3 gig available (Taskmanager doesn't
easily show where the stolen gig went), only a bit more than 2
gig is "available". Again, I'm not personally interested in
theoretical discussion, as I'm a strict pragmatist.
So, if there are memory management settings other than the
defaults of XP Pro SP2 I should alter to improve my overall
performance, please let me know where the controls are.
Thanks.
It's much more than 4GB, but less than the theoretical max
for such things of 2**64.
I said I didn't know, OK?
