A value that starts "1", "y", or "Y" enabled incremental mode
permanently (any value was allowed formerly), while a value that
starts "0", "n", or "N" causes incremental-mode requests to be
ignored.
When a major GC triggers finalization, another major
GC is scheduled immediately on the grounds that the
finalizer may release other values. That was important
at once time, but the finalization and weak-reference
implementation has improved to the point where the
extra ful GC no longer seems necessary or useful.
Originally, generation 1/2 was intended to delay major
collections when the heap is especially large. It doesn't
seem to be effective in that case, and it can slow down
minor GCs, so continue to use it only in incremental
mode (where it helps significantly with fragmentation).
At the completion of an incremental major GC, if incremental
mode wasn't requested recently, schedule an immediate major
GC to reduce the heap back to its normal footprint.
When custom categories are used in older versions, raco setup will
report a warning, but the documentation will still appear under the
Miscellaneous section. Thus, this is a backwards compatible
implementation of the idea.
A collection's "info.rkt" might have `(define compile-omit-paths
'all)` but also other setup actions, so don't completely ignore
a collection directory just because there's nothing to compile.
Also, make nursery 1/4 as big in incremental mode, and
correspondingly tune the amount of work to perform per
collection by 1/4 its old value. Using generation 1/2
reduces fragmentation that would otherwise be increase
by a smaller nursery.
The main intent of this change is to raise the buffer size
for ARM, but that would leave only 32-bit x86 at size 100, so
just make it size large for all machines.
Port `examples`, `interactions`, etc., to use the new `examples`
form of `scribble/examples`. The main intended effect is to ensure
that errors are produced by examples only as specifically
indicated.
