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Re: Making rtxes use less memory (sometimes!)


"Zack Weinberg" <zack@codesourcery.com> writes:
> Richard Sandiford <rsandifo@redhat.com> writes:
> > Here's the sort of speed-up I get when compiling mips.i
> > using a mips64-linux-gnu native:
> >
> >      -O0
> > 	     before         after
> >      real    0m31.478s      0m29.830s
> >      user    0m31.270s      0m29.670s
> >      sys     0m0.200s       0m0.130s
> >
> >      -O1
> > 	     before         after
> >      real    0m16.364s      0m15.465s
> >      user    0m16.220s      0m15.270s
> >      sys     0m0.140s       0m0.190s
> >
> >      -O2
> > 	     before         after
> >      real    0m7.804s       0m7.104s
> >      user    0m7.690s       0m7.030s
> >      sys     0m0.100s       0m0.070s
> >
> > (these are reproducable to within ~0.1s).
> 
> Do you have the -O numbers backward?  It seems odd that -O0 would be
> four times slower than -O2.

Doh!  You're right, of course.

> This is OK.

Applied, thanks.

Richard


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