To swap or not to swap that is the question

[chris at logsoft.com (Chris Marget)]

> My .02 quatloos about swap is:  Swap is what you use when you don't
> have any other place to put it.

indeed.

> Old SunOS requested 2x swap, and would not work without at least 1x
> memory available in swap.

sort of.  sunos could run entirely without swap, just like any other
unix, but if you wanted to use swap, your swap space *had* to be at
least as big as physical ram.

the reason for this was that the definitions were a little different.
in modern systems, total virtual memory size is RAM + swap.  under
sunOS < 5, total virtual memory size = swap space.  every byte in VM
was on disk and some of those bytes were *also* in RAM.  nowadays,
any memory location is either in RAM or swap.  Not both.

/chris