si:full-gc & Optimize World

["David L. Andre" <DLA@jasper.scrc.symbolics.com>]

    Date: Tue, 2 Aug 88 10:42 EDT
    From: steinmetz!VEGA!jka@uunet.UU.NET (Jim Aragones)

    I've just been rewriting our world-building script to do some new things
    and noticed that the documentation implies that you can't use
    (SI:REORDER-MEMORY) or (SI:ENABLE-WHO-CALLS :ALL-NO-MAKE) without
    calling (SI:FULL-GC), but the documentation says:

Neither of these inferences are true.  Where did you find them?

    "It is not useful to perform an Incremental Disk Save after running
    si:full-gc. Use a complete disk save."

    "You should use si:reorder-memory on IDS worlds only if the parent world
    has itself been optimized or if the parent world does not need
    optimizing."

    Assuming that I want to reorder memory or enable-who-calls for an
    incremental world load, how do I loose (or win) by using (GC-IMMEDIATELY)
    instead of (SI:FULL-GC)?  I could make an educated guess, but I'd rather
    have facts if people have them.

(GC-IMMEDIATELY) modifies every page containing dynamic objects, and
every page which references dynamic objects.  It will increase your IDS
size by that amount.  (That amount may not be much, but will likely be
large, particularly for second-generation IDS's.)  Running FULL-GC
modifies all pages, so the IDS would be as large as a complete world.

What are you trying to do?  If you want to enable who-calls in an
incremental world, use (si:enable-who-calls :all).  If you want to
reorder memory in an incremental world, use (si:reorder-memory).

    -Jim Aragones