Re: ATTN RMS,Moon

[MOON@MIT-AI]

At least in version 6, if you create and forget about a lot of windows,
TV-PC-PPR-LIST gets to be very long.  Furthermore the pcs ppr are in
WORKING-STORAGE-AREA, mixed in with other things like bit save arrays.
This then causes lots of page thrashing in TV-NOTE-INPUT, possibly
in other places.  Only pcs ppr for exposed windows should be on this list;
fixing this requires some interaction between windows and TVs.  If the
window system calls TV-DEACTIVATE-PC-PPR, perhaps it should change TV-PC-PPR-LIST.
Alternatively, perhaps that list should be flushed and TV-NOTE-INPUT should
run off of EXPOSED-WINDOWS (doing something appropriate during cold loading
before the window system is initialized.)

In any case, bit save arrays may need to be in their own area.

There is a great deal of page thrashing when I create several windows
at once, amounting to a real time delay of over 5 seconds.  Possibly bit
save arrays should be paged out right after they are created, or not created
until they are needed (I thought this was the case).  I haven't fully investigated
all this thrashing yet, but clearly something is wrong.