On Wed, Jan 22, 2020 at 5:03 PM Isuru Fernando <isu...@gmail.com> wrote: > > > On Arch, does cblas.pc exist? > > Yes.
Thanks. I wonder what on Arch is the output of pkg-config --modversion X for X in [cblas,blas,lapack,openblas] > > > this is system-dependent. > > Yes, that's why we need to have fallbacks. > > Isuru > > On Wed, Jan 22, 2020 at 11:00 AM Dima Pasechnik <dimp...@gmail.com> wrote: >> >> On Wed, Jan 22, 2020 at 4:17 PM Isuru Fernando <isu...@gmail.com> wrote: >> > >> > > maybe they split openblas.so into separate sections for an unclear to me >> > > reason, but most applications I know uses cblas, blas and lapack, so >> > > they need to link them all anyway. >> > >> > True, but in sage you are copying `openblas.pc` to `cblas.pc` and >> > `lapack.pc` which is wrong. `openblas.pc` should only be expected to >> > provide blas. >> >> this is system-dependent. Debian and Fedora have no libcblas and no >> cblas.pc, cblas is provided by openblas. >> Some *BSD systems have libcblas conflcting with libopenblas. >> >> On Arch, does cblas.pc exist? >> >> >> > >> > A solution would be to check that `blas.pc`, `cblas.pc`, `lapack.pc` are >> > already on the system and if not copy `openblas.pc` to the three names. >> > >> > Isuru >> > >> > On Wed, Jan 22, 2020 at 10:14 AM Isuru Fernando <isu...@gmail.com> wrote: >> >> >> >> > errors we see here, regarding absence of certain openmp functions in >> >> > cblas, seem to indicate that cblas on Arch does not come from openblas. >> >> > perhaps what we see are reference cblas and blas from openblas >> >> > installed at the same time, in error. >> >> >> >> Can you please explain more? As I said earlier, it doesn't matter where >> >> CBLAS is coming from. I checked in Arch linux and cblas is linked to >> >> openblas. >> >> >> >> [root@50586643ff22 /]# ldd /usr/lib/libcblas.so.3 >> >> linux-vdso.so.1 (0x00007ffd2f7bb000) >> >> libblas.so.3 => /usr/lib/libblas.so.3 (0x00007f848f079000) >> >> libc.so.6 => /usr/lib/libc.so.6 (0x00007f848eeb2000) >> >> libm.so.6 => /usr/lib/libm.so.6 (0x00007f848ed6c000) >> >> libpthread.so.0 => /usr/lib/libpthread.so.0 (0x00007f848ed4a000) >> >> libgomp.so.1 => /usr/lib/libgomp.so.1 (0x00007f848ed11000) >> >> /usr/lib64/ld-linux-x86-64.so.2 (0x00007f84902dc000) >> >> libdl.so.2 => /usr/lib/libdl.so.2 (0x00007f848ed0c000) >> >> >> >> [root@50586643ff22 /]# ls -al /usr/lib/libblas.so.3 >> >> lrwxrwxrwx 1 root root 22 Aug 20 10:35 /usr/lib/libblas.so.3 -> >> >> libopenblasp-r0.3.7.so >> >> >> >> >> >> Isuru >> >> >> >> On Wed, Jan 22, 2020 at 10:09 AM Dima Pasechnik <dimp...@gmail.com> wrote: >> >>> >> >>> >> >>> >> >>> On Wed, 22 Jan 2020, 15:59 Isuru Fernando, <isu...@gmail.com> wrote: >> >>>> >> >>>> > But Arch does not do this, it instead provides dog-slow CBLAS and >> >>>> LAPACK, built >> >>>> from another (reference, i.e. no assembler, no optimisation) >> >>>> implementation. >> >>>> >> >>>> This is simply not true. CBLAS's performance does not depend on which >> >>>> implementation it comes from. CBLAS's performance depends on the >> >>>> underlying BLAS implementation and on ArchLinux, when OpenBLAS is >> >>>> installed, CBLAS uses OpenBLAS as the underlying BLAS implementation. >> >>>> In fact, OpenBLAS uses the CBLAS code from Netlib's reference >> >>>> implementation. >> >>> >> >>> >> >>> errors we see here, regarding absence of certain openmp functions in >> >>> cblas, seem to indicate that cblas on Arch does not come from openblas. >> >>> perhaps what we see are reference cblas and blas from openblas installed >> >>> at the same time, in error. >> >>> >> >>> maybe they split openblas.so into separate sections for an unclear to me >> >>> reason, but most applications I know uses cblas, blas and lapack, so >> >>> they need to link them all anyway. >> >>> >> >>> >> >>>> >> >>>> As for LAPACK, in OpenBLAS, they have implemented a handful of >> >>>> functions to use OpenBLAS internals to make it parallel, but most of >> >>>> the LAPACK functions are from Netlib's Reference implementation. So, >> >>>> when ArchLinux is using LAPACK from netlib, they are losing out on only >> >>>> a few LAPACK functions. >> >>>> >> >>>> Isuru >> >>>> >> >>>> On Wed, Jan 22, 2020 at 9:27 AM Dima Pasechnik <dimp...@gmail.com> >> >>>> wrote: >> >>>>> >> >>>>> >> >>>>> >> >>>>> On Wed, 22 Jan 2020, 15:12 Vincent Delecroix, >> >>>>> <20100.delecr...@gmail.com> wrote: >> >>>>>> >> >>>>>> Le 22/01/2020 à 15:41, Dima Pasechnik a écrit : >> >>>>>> > On Wed, Jan 22, 2020 at 2:31 PM Vincent Delecroix >> >>>>>> > <20100.delecr...@gmail.com> wrote: >> >>>>>> >> >> >>>>>> >> I had the same annoying trouble... Is it really a bug in arch? I >> >>>>>> >> don't >> >>>>>> >> find anywhere where libopenblas is supposed to provide the LAPACK >> >>>>>> >> interface. To me it is just true for SageMath and false for >> >>>>>> >> Archlinux. >> >>>>>> > >> >>>>>> > well, a "bug", in the sense that their openblas configuration just >> >>>>>> > does not make any sense, >> >>>>>> > because if you install a highly optimised BLAS implementation, >> >>>>>> > which can also >> >>>>>> > provided a highly optimised CBLAS and LAPACK, in a sane world you'd >> >>>>>> > install them >> >>>>>> > too. But Arch does not do this, it instead provides dog-slow CBLAS >> >>>>>> > and >> >>>>>> > LAPACK, built >> >>>>>> > from another (reference, i.e. no assembler, no optimisation) >> >>>>>> > implementation. >> >>>>>> > This causes Sage's logic, which expects that openblas will also >> >>>>>> > provide CBLAS and LAPACK, to fail. >> >>>>>> > >> >>>>>> > Yes, it is possible to make tests to detect this silly setup, but I >> >>>>>> > think that everyone's time >> >>>>>> > is much better spent if Arch provided a full build of openblas, with >> >>>>>> > CBLAS and LAPACK, >> >>>>>> > instead. >> >>>>>> >> >>>>>> Hence there are two bugs >> >>>>>> >> >>>>>> * a "logical" bug in archlinux that provides a slow lapack for >> >>>>>> (apparently) no good reason >> >>>>>> >> >>>>>> * a structural bug in SageMath that assumes that openblas does >> >>>>>> install the LAPACK interface >> >>>>>> >> >>>>>> >> >>>>>> I tend to agree that the resolution of any of these two would solve >> >>>>>> the compilation. But in an ideal world we would just solve the two. >> >>>>> >> >>>>> >> >>>>> a meaningful resolution of this would be to test openblas for lapack >> >>>>> and cblas capacities. >> >>>>> >> >>>>> this is relatively easy, and would result in openblas on Arch being >> >>>>> built by Sage. >> >>>>> >> >>>>> as far as expanding this to other implementations of blas/lapack, >> >>>>> it is harder. >> >>>>>> >> >>>>>> >> >>>>>> >> >>>>>> >> >> >>>>>> >> Le 13/01/2020 à 11:44, Dima Pasechnik a écrit : >> >>>>>> >>> On Sat, Jan 11, 2020 at 11:35 AM arojas <nqn1...@gmail.com> wrote: >> >>>>>> >>>> >> >>>>>> >>>> El sábado, 11 de enero de 2020, 11:23:32 (UTC+1), Dima Pasechnik >> >>>>>> >>>> escribió: >> >>>>>> >>>>> >> >>>>>> >>>>> >> >>>>>> >>>>> >> >>>>>> >>>>> On Sat, 11 Jan 2020, 10:19 arojas, <nqn...@gmail.com> wrote: >> >>>>>> >>>>>> >> >>>>>> >>>>>> I suspect this may be due to our openblas package only >> >>>>>> >>>>>> providing libblas.so (not libcblas.so or liblapack.so, which >> >>>>>> >>>>>> in our case come from the netlib blas). >> >>>>>> >>>>> >> >>>>>> >>>>> >> >>>>>> >>>>> Are you saying that your libopenblas.so does not provide >> >>>>>> >>>>> everything that is in openblas by default? >> >>>>>> >>>>> >> >>>>>> >>>>> This is largely defeating its purpose. >> >>>>>> >>>>> Sage's openblas does provide the cblas and lapack capabilities. >> >>>>>> >>>> >> >>>>>> >>>> >> >>>>>> >>>> In that case, openblas' spkg-configure should check whether >> >>>>>> >>>> cblas symbols are provided by the system openblas, and if not it >> >>>>>> >>>> should compile sage's one. It shouldn't unconditionally assume >> >>>>>> >>>> that that's always the case. >> >>>>>> >>> >> >>>>>> >>> I maintain that it's a bug in Arch, that libopenblas cannot be >> >>>>>> >>> used as >> >>>>>> >>> a replacement of cblas and lapack, for it defeats its purpose. >> >>>>>> >>> Most uses of BLAS routines are either via LAPACK, or from C/C++, >> >>>>>> >>> via cblas. >> >>>>>> >>> >> >>>>>> >>> >> >>>>>> >>> >> >>>>>> >>>> >> >>>>>> >>>> -- >> >>>>>> >>>> You received this message because you are subscribed to the >> >>>>>> >>>> Google Groups "sage-devel" group. >> >>>>>> >>>> To unsubscribe from this group and stop receiving emails from >> >>>>>> >>>> it, send an email to sage-devel+unsubscr...@googlegroups.com. >> >>>>>> >>>> To view this discussion on the web visit >> >>>>>> >>>> https://groups.google.com/d/msgid/sage-devel/a1516e56-ab25-410e-be0f-75a7a6713466%40googlegroups.com. >> >>>>>> >>> >> >>>>>> >> >> >>>>>> >> -- >> >>>>>> >> You received this message because you are subscribed to the Google >> >>>>>> >> Groups "sage-devel" group. >> >>>>>> >> To unsubscribe from this group and stop receiving emails from it, >> >>>>>> >> send an email to sage-devel+unsubscr...@googlegroups.com. >> >>>>>> >> To view this discussion on the web visit >> >>>>>> >> https://groups.google.com/d/msgid/sage-devel/dbf38073-170b-4c7d-63b9-d4429a8794e2%40gmail.com. >> >>>>>> > >> >>>>>> >> >>>>>> -- >> >>>>>> You received this message because you are subscribed to the Google >> >>>>>> Groups "sage-devel" group. >> >>>>>> To unsubscribe from this group and stop receiving emails from it, >> >>>>>> send an email to sage-devel+unsubscr...@googlegroups.com. >> >>>>>> To view this discussion on the web visit >> >>>>>> https://groups.google.com/d/msgid/sage-devel/e3ad609d-8d21-bb10-2876-367fdf1b7e24%40gmail.com. >> >>>>> >> >>>>> -- >> >>>>> You received this message because you are subscribed to the Google >> >>>>> Groups "sage-devel" group. >> >>>>> To unsubscribe from this group and stop receiving emails from it, send >> >>>>> an email to sage-devel+unsubscr...@googlegroups.com. >> >>>>> To view this discussion on the web visit >> >>>>> https://groups.google.com/d/msgid/sage-devel/CAAWYfq3p7x9KmwHLmhjOtuoy_3PdsohHN6RJ0fp0Bzxv-wHODQ%40mail.gmail.com. >> >>>> >> >>>> -- >> >>>> You received this message because you are subscribed to the Google >> >>>> Groups "sage-devel" group. >> >>>> To unsubscribe from this group and stop receiving emails from it, send >> >>>> an email to sage-devel+unsubscr...@googlegroups.com. >> >>>> To view this discussion on the web visit >> >>>> https://groups.google.com/d/msgid/sage-devel/CA%2B01voO3C4pdc5gbU02KzhR1DuzZ0Gwv2n6CoSukODeEqFfEjQ%40mail.gmail.com. >> >>> >> >>> -- >> >>> You received this message because you are subscribed to the Google >> >>> Groups "sage-devel" group. >> >>> To unsubscribe from this group and stop receiving emails from it, send >> >>> an email to sage-devel+unsubscr...@googlegroups.com. >> >>> To view this discussion on the web visit >> >>> https://groups.google.com/d/msgid/sage-devel/CAAWYfq1qxH7SUEWy%2BP3CQ_WeCimK_ByX3Q_HNz4Li%2BvwZCznYA%40mail.gmail.com. >> > >> > -- >> > You received this message because you are subscribed to the Google Groups >> > "sage-devel" group. >> > To unsubscribe from this group and stop receiving emails from it, send an >> > email to sage-devel+unsubscr...@googlegroups.com. >> > To view this discussion on the web visit >> > https://groups.google.com/d/msgid/sage-devel/CA%2B01voO-GZJ9gSgsQ-N4stwfkvonWz2aDU%2Bcpv6ViJ8eN%3D0wNw%40mail.gmail.com. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "sage-devel" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to sage-devel+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/sage-devel/CAAWYfq3D4YGM2HR7SORfjDFhkjQ%3Dm1Jn4CsEwmioF-18poxRdQ%40mail.gmail.com. > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/CA%2B01voO%2BWkpafvpuUfLmGw8qDZ1qFMwzoA6HFBBBiZWYGdTqpw%40mail.gmail.com. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. 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