gcc 3.3 garbage collector defaults

[Zack Weinberg]

Matt Austern <austern@apple.com> writes:

> When I compare 3.2 and 3.3 on the same file and the same
> machine, 3.3 is much slower than 3.2 and a good part of the
> extra time, according to -ftime-report, is from the gc.  If
> those measurements are right (and I think they probably are,
> since several other people report similar results), then
> there aren't a whole lot of possibilities for what caused
> the regression.  We now know it wasn't the gc parameters.
> What possibilities haven't we ruled out yet?

My bet would be differing allocation patterns causing the GC to do
more work in 3.3.  If you provide me with a test case I can try
various profiling tools and give a more definite answer.

zw