On Wed, Dec 8, 2010 at 6:59 PM, Prashanth S <prashant...@samsung.com> wrote: > > Dear All > > Our team in Samsung collected some performance metrics for the following > 3 GCC cross compilers > > Gentoo Complier(part of Chrome OS Build Environment) > GCC 4.4.1 (Code Sourcery). > Linaro (gcc-linaro-4.5-2010.11-1) > > Flags used to Build Linaro Tool chain > used Michael Hope Script .Just modified "GCCFLAGS = --with-mode=thumb > --with-arch=armv7-a --with-float=softfp --with-fpu=neon > --with-fpu=vfpv3-d16" > > Using the above three tool chains we compiled the kernel of Chrome OS and > did Coremark Performance test.(With same optimisation flag mentioned in the > attachment) > Test Environment for all the three are the same. > > > My Questions > > Is there any build options that I am missing while I am building the Cross > Compiler? > Else is this performance degradation is a know issue and is the tool chain > group working on it?.(If so whom to contact?) > > Any Pointers from you would be of great help to me. > If you need any further details also do ping me
Hi Prashanth. I'm a bit confused, as I'm talking with Sree from Samsung about the same topic at the moment. Here's what I said to him: """ We run coremark along with a range of other tests with each continuous build. On a OMAP3 (Cortex-A8), we score 1570, plain GCC 4.4.4 scores 1431, and CodeSourcery GCC scores 1670. Note that all values are estimates, to fit in with the coremark reporting rules. I'm not sure coremark is the best choice of benchmark as it's a synthetic benchmark with a deeply embedded focus. For comparison, we are 5 % ahead of CodeSourcery on pybench, up to 17 % ahead on h.264 decode, and 3 % ahead on Ogg/Vorbis decode. A large part of this is due to the upstream improvements between 4.4 and 4.5. Given that, I'm currently looking into the difference between CodeSourcery GCC and Linaro GCC as there's a significant difference to be explained. """ Since then I've tracked it down further. It seems to be a regression between 4.4 and 4.5. I'm looking into running a wider suite of benchmarks on an A9 to decide on what to do next. Hope that helps, -- Michael _______________________________________________ linaro-toolchain mailing list linaro-toolchain@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-toolchain
