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Re: Just a reminder of serious open 3.3 PRs
Op ma 14-04-2003, om 22:45 schreef Gerald Pfeifer:
> On Sun, 6 Apr 2003, Steven Bosscher wrote:
> > The two three are serious compile time regressions from 3.2 that should
> > be show stoppers for 3.3 according to the GCC release criteria. .
> >
> > opt/8361 [3.3/3.4 regression] C++ compile-time performance regression
> > This is a 70% slowdown wrt. 3.0.4, and 30% wrt. 3.2.1. It was blamed
> > on garbage collection and other things, but no real analysis was done
> > for this problem. The "official" rule from the release criteria
> > states that "A release candidate's compile-time should not exceed
> > GCC 2.95.3 by more than 15% ..." Here we have two times the maximum
> > slowdown with respect to the latest official release.
>
> Here is a comparison of how GCC evolved (snapshots around mid of last
> week):
>
> -O0 -O1 -O2 -O3
> GCC 3.0.4 27.95 44.52 56.57 56.48
> 3.2-branch 29.87 +7% 54.28 +22% 70.95 +25% 75.29 +33%
> 3.3-branch 29.09 +4% 57.11 +30% 78.99 +40% 81.61 +44%
> mainline 27.06 56.09 77.77 82.02
>
> Here we have +30% when comparing against 3.0.4 for -O1, and +40% for -O2!
Yes -- but what is a bit surprising (at least, to me) is that most of
the slowdown is already introduced at -O1.
What do the time reports tell you, which parts are the biggest losers?
I assume you left the default GC params in for 3.3 and mainline?
Greetz
Steven