This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Loop unrolling-related SPEC regressions?
Laurent Guerby <guerby@acm.org> writes:
> I just merged your base results with:
>
> <http://www.spec.org/osg/cpu2000/results/res2000q4/cpu2000-20001204-00426.asc>
>
> GCC S G/S SP G/SP
> 164.gzip 461 472 0.976 563 0.818
> 175.vpr 259 255 1.015 285 0.908
> 176.gcc 323 248 1.302 355 0.909
> 181.mcf 180 194 0.927 196 0.918
> 186.crafty 524 632 0.829 678 0.772
> 197.parser 325 372 0.873 373 0.871
> 252.eon 642 692 0.927 1056 0.607
> 253.perlbmk 495 668 0.741 720 0.687
> 254.gap 366 441 0.829 441 0.829
> 255.vortex 410 702 0.584 731 0.560
> 256.bzip2 305 335 0.910 343 0.889
> 300.twolf 284 340 0.835 360 0.788
>
> GCC = GCC base, S = SPEC base, SP = SPEC peak
>
> This was with the closest SPEC run I found, however
> the MHz are different, so I don't know if a rescale is needed:
>
> SPEC web: CPU: 1.2GHz AMD Athlon processor A1200AMT3B
> Andreas : CPU MHz: 1102.541
A rescale is needed.
Better take these values that I measured under Linux with the same CPU
as in
http://www.spec.org/osg/cpu2000/results/res2001q2/cpu2000-20010519-00651.asc
(use those values for comparison!):
Compiler GCC 3.1 from CVS of 2001-11-07
Base flags: -O3 -march=athlon -fomit-frame-pointer
Peak flags: -O3 -march=athlon -fomit-frame-pointer, FDO: Pass1:
-fprofile-arcs, Pass2 -fbranch-probabilities
Estimated Estimated
Base Base Base Peak Peak Peak
Benchmarks Ref Time Run Time Ratio Ref Time Run Time Ratio
164.gzip 1400 274 511 1400 264 530
175.vpr 1400 451 310 1400 464 302
176.gcc 1100 286 384 1100 275 400
181.mcf 1800 829 217 1800 897 201
186.crafty 1000 171 585 1000 163 614
197.parser 1800 470 383 1800 465 387
252.eon 1300 211 616 1300 210 618
253.perlbmk 1800 321 562 1800 309 583
254.gap 1100 235 467 1100 228 482
255.vortex 1900 401 474 1900 379 501
256.bzip2 1500 378 397 1500 398 377
300.twolf 3000 908 331 3000 892 336
SPECint_base2000 420
SPECint2000 424
Hardware: Dual AMD Athlon 1.2 GHz, 1 GB Memory, SCSI system
Software: SuSE Linux 7.3.
> Apparent weaknesses on base are vortex and perlbmk, has
> anyone looked at them? perl might be interesting, 25%
> base performance hit on such a complex piece of free software,
> there must be some critical interpreter piece of code
> completely miscompiled by CVS GCC (performance-wise).
>
> Any perl hacker willing to zoom on it?
> Does anyone know if it is a performance regression from previous GCC?
>
> I assume eon and vortex are easy targets for "one
> optimisation gets all" and might be less interesting
> to look at.
Andreas
--
Andreas Jaeger
SuSE Labs aj@suse.de
private aj@arthur.inka.de
http://www.suse.de/~aj