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Re: SSE Level 3 drop in gemm
Hello again! Sorry to write so frequently, but this is almost wrapped
up, and I'd like to get it out quickly if possible, while its fresh in
R Clint Whaley <email@example.com> writes:
> >Now I have a different issue. My kernel likes nb=56 the best. Atlas
> >standard likes nb=64. And this is what I get in sMMRES:
> >intech20:/mnt/i19/f/debian/mm/atlas/tmp/atlas-3.1.2D/tune/blas/gemm/Linux_fpic$ cat res/sMMRES
> >MULADD LAT NB MU NU KU FFTCH IFTCH NFTCH MFLOP
> > 0 2 64 5 1 64 0 5 1 371.46
> >ATL_sgemm_SSE.c "CM"
> > 1 1 64 2 2 64 0 4 1 617.61
> The best solution is probably to add another case to scases.dsc. I guess
> you have a line that looks something like this right now:
> 0 1 1 1 1 1 2 2 64 ATL_sgemm_SSE.c "CM"
> add a second line, with the explicit 56 blocking factor:
> 0 -56 -56 -56 1 1 2 2 64 ATL_sgemm_SSE.c "CM"
OK. Thanks! But even with the sMMRES above, doing the make install
made a lib without my kernel. bin/arch/xsl3blastst gives 370 MFLOPS. :-(
> And that should force ATLAS time using your best blocking factor, which should
> then be selected . . . In the long run, I think it makes sense to have ATLAS
> do this: if a user-contributed kernel is found to beat the generated kernel,
> run through the list of possible NBs again, to find the best. I'll look at
> adding that while I'm doing the cleanup stuff . . .
> >Also, any sugegstions on the unrolling issue? If I put in macros to
> >unroll k at differing levels depending on KB, would that confuse the
> >search engine? Should install faster than having 3 different k unroll
> >kernels to time.
> I don't think it would confuse the script, but you'd have to force the
> different NB's at present via a technique like above. Should work like
> a charm if I add the NB search, though . . .
Just a reminder, one other outstanding issue is the data alignment.
Setting Atlas_Cachelen did not seem to affect the mmtst.c or fc.c
programs. Am I missing something here?
Camm Maguire firstname.lastname@example.org
"The earth is but one country, and mankind its citizens." -- Baha'u'llah