[project @ 1999-02-05 14:48:01 by simonm]

[ repeating commit, message got lost last time ]

- Scavenge each older generation immediately after traversing its
  mutable list.

- Make the first GC a major one: it doesn't cost much, and we get
  to garbage collection 'main' straight away.

- Change the order of scavenging to try to minimise the size of
  the mutable lists.