[plt-scheme] 3m defaults to --enable-account

Eli Barzilay <eli at barzilay.org> writes:

> On Jan 16, Jim Blandy wrote:
> > 
> > Matthew Flatt <mflatt at cs.utah.edu> writes:
> > > If you need the old 3m collector for some reason, configure with
> > > --enable-compact. As the name of this flag suggests, the old 3m
> > > collector tends to keep a smaller memory footprint than the
> > > now-default collector, but the difference between the two
> > > collectors is much less significant than the difference between 3m
> > > "precise" collection and conservative collection. The old
> > > collector does not support memory accounting.
> > 
> > I'm curious why you folks switched from conservative to precise GC.
> > (Not questioning the decision at all, just wondering.)  Do you have
> > a writeup somewhere about the motivation?  Have you measured the
> > performance impact?
> 
> It's only the default for the precise collector version (3m) that
> changed -- if you don't use 3m, then nothing changed.

That's not quite why I was asking.  I've had the precise
vs. conservative debate going on in my head for many years now, and I
was hoping you folks' attack on the question might help clarify things
for me.