> http://www.racesimcentral.net/:
> Swap-File myth #1:
> Create a permanent swapfile 2 1/2-3 times the amount of physical
> memory.
> Fact: Virtual memory (Swap-File) is a substitute for physical memory.
> Common sense tells you the more physical memory you have, the less
> virtual memory you need. Conversely (all other things being equal) the
> less physical memory you have the more virtual memory you will need.
Well I believe the 2,5x rule of thumb is:
If your system runs fine with a 2,5x RAM size page file under heavy
"normal" load then you've reached some sort of optimal memory point:
Less memory requires a bigger swap file and results in heavy paging (even
inside one application) and a huge performance decrease.
More memory OTOS will increase the systems performance under normal load
only slightly because most things will fit into RAM i.e. paging mostly
occurs when the user start a new program or (infrequently) switches
between large applications.
Of course more RAM (and thus a relativly smaller page file) won't hurt
performance - however the gain isn't that dramatic during normal use.
OTOH Memory intensive applications (like some games) will still benefit a
lot from more memory - up to the point where you don't need a swap file
at all because all your data and apps fit into RAM.
In short: The rule is not: "I have 128 MB RAM so I need 300 MB swap" but
"if the system needs a page file 2,5 times the RAM size to run under heavy
load then you have enough memory for a smooth normal use".
That's how _I_ understand that rule, anyway.
Personally I'd like to have my min and max size the same for this very
reason. When I get the out of memory error I know that my page file is
"full" and that it might be a good idea to avoid using that many programs
at the same time or buy some more RAM.
Just my 0.02
Martin