Jean writes:
> So from what I understand, transient free space is either data or
> instructions or programs not often used by the system and from  memory
> pressure is temporarily stored on disk.

It will only be data that isn't part of a file.  Program instructions always
come from program files (or XLs etc.), and code cannot be modified while
it's being executed, so when code in memory is overwritten, it can just be
thrown away, and when you need to get it bac, you just copy it in from the
program file (or XL, etc.).  Thus every program and library file that is
"loaded" is actually part of your "swap space" (though read-only) if you
want to look at it that way.

Also again the fact that you see disk allocated to transient space does not
mean that anything has been "swapped out" there.  The system must make sure
that it has enough disk space allocated JUST IN CASE in needs to swap out
the data.  If it needed to swap something out and there was no available
disk space, that would be Bad(tm).

> If I have only 3% of the available
> 10Gbytes of reserved transient space used then and my system is maxed out at
> 1.5 Gybtes of Ram, I will hardly gain any speed by moving transient space to
> a ram disk.

Correct.

> Another Question is:  Data that is seldom used in memory gets trashed out,
> does it go into transient free space first or is it simply written over in
> memory?

The hardware keeps track of whether each page in memory has been modified or
not.  If the data have not been changed, then the page can simply be
overwritten with new data without first writing the page out to transient
space.  If the page has been modified, then the system will have to arrange
to write it to disk into the appropriate place (either transient space for
things like your stack/heap, or back into the file it came from if it is
part of a data file, etc.).

G.