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Re: RAM question for everyone!



Les wrote:
On Fri, 2009-01-23 at 11:07 -0500, Mark Haney wrote:

I guess I do not comprehend the issue of more memory stressing low
memory?

I know that a 32 bit system is constrained in addressing to something
like 4G, due to the intel addressing architecture, and 32 bit
constraint, so applications were developed to go beyond that.  But given
that the system maps the logical memory to physical memory, and some can
do this via hardware, how does adding more memory add more stress?  If
the system is running the application now, the basic change is reducing
swapping to disk, is it not?

Regards,
Les H
While the 32bit machine can physically use more then 4G of memory the I/O hardware can only move stuff in and out of the first 4G. Therefore any I/O that a process in "high" memory is doing has to be bounced/buffered through somewhere under the 4G mark. The CPU ends up doing all the copying and the memory is now committed to I/O buffering rather than programs or data.

Jeff Voskamp
Feel free to correct me if I'm wrong (and I know you will).


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