Today, =?Utf-8?B?THVrZSBDaGFsbWVycw==?= made these interesting
comments ...
Hi all,
just a quick one, what are the implications of increasing the
virtual memory?
Many thanks
You get virtually the same performance increase as increasing
real memory.
Huh?
Virtual memory is just that - an illusion created by seamlessly
copying data to/from "memory" to some slower-but-larger-capacity
device such as a HD or even to streaming tape. So, while VM
capacity is limited only by the O/S and how much space you're
willing to devote to it, the more the system swaps to the slower
media, the more and more slowly your system will run.
Then, too, is a syndrome called "thrashing" where the CPU is
attempting to read/write/read/write ... continuously as real
memory fills, programs or data are swapped out, the next piece
swappin in for a few CPU cycles, etc. You notice that happening
when you see or hear your HD grinding away and not much else
happening.
The cure for all of this, within the other limits of your current
system, is to get more real memory. There's a number of other
considerations, of course, but doubling real memory will have an
immediate and noticeable improvement in performance, that is,
except that I don't call Windows "Windoze" for nothing - it ain't
my idea of an efficient O/S for either disc or memory access, but
that's a story best left on the side of the road.