[HM] B&W G3 speed question in the last three days. Well here are my findings.

Nevin Steindam thenevin at ameritech.net
Fri Feb 14 06:35:37 PST 2003

>As I have used TOP I found that I have just over 6 meg of memory left
>with these applications open.

Actually, OS X's virtual memory system is really good at keeping memory
"paged out" behind the scenes.  I'm sure that you are actually using more
than 256 megs of memory, but parts that have not been used recently are
being cached to the disk to make room for the parts ("pages") that are
currently being accessed frequently.  The system tries to keep a few
megabytes free at all times for flexibility.  But try watching TOP while
you open new programs.  The amount of free memory will go down a little, if
at all.  And you'll never get it down to 0 Megs free, or get an out of
memory error.

The best way to tell how desperately you need memory is to see if you can
notice slowdowns caused by not having enough.  You know the long pause
(accompanied by loud disk reads) that you get when you switch to a program
that you haven't used in a little while?  That's caused by the system
needing to move lots of cached memory back into RAM.  You may get little
effects like that sometimes, just switching between windows or something
like that.  If that happens often enough to be annoying, then more RAM will
fix it.  If you don't know what I'm talking about, then you're probably
doing just fine with your 256 megs.

But I can't see how 256 would possibly be enough, so I expect that you need
more :)


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