On Fri, Oct 14, 2011 at 4:12 AM, David Gilbert <david.gilb...@linaro.org> wrote: > I've just tried rerunning some benchmarks on my panda, which I > reinstalled recently and am getting > some odd behaviour: > > The kernel is 3.0.0-1404-linaro-lt-omap > > For example: > simple_strlen: ,102400, loops of ,62, bytes=6.054688 MB, transferred > in ,20324707.000000 ns, giving, 297.897898 MB/s > simple_strlen: ,102400, loops of ,32, bytes=3.125000 MB, transferred > in ,7904053.000000 ns, giving, 395.366782 MB/s > simple_strlen: ,102400, loops of ,16, bytes=1.562500 MB, transferred > in ,7354736.000000 ns, giving, 212.448142 MB/s > simple_strlen: ,102400, loops of ,8, bytes=0.781250 MB, transferred in > ,91553.000000 ns, giving, 8533.308575 MB/s > simple_strlen: ,102400, loops of ,4, bytes=0.390625 MB, transferred in > ,1495361.000000 ns, giving, 261.224547 MB/s > simple_strlen: ,102400, loops of ,2, bytes=0.195312 MB, transferred in > ,1983643.000000 ns, giving, 98.461518 MB/s > > Note the 8 byte one apparently 40 times faster, and for true oddness: > > smarter_strlen_ldrd: ,102400, loops of ,62, bytes=6.054688 MB, > transferred in ,3936768.000000 ns, giving, 1537.984331 MB/s > smarter_strlen_ldrd: ,102400, loops of ,32, bytes=3.125000 MB, > transferred in ,0.000000 ns, giving, inf MB/s > smarter_strlen_ldrd: ,102400, loops of ,16, bytes=1.562500 MB, > transferred in ,4180909.000000 ns, giving, 373.722557 MB/s > > Now, while I like infinite transfer rates, I suspect they're wrong.
These tests are short in general at roughly 4 ms. Perhaps you're running into a scheduling resolution problem due to a low HZ value, dynamic ticks is wrong, high resolution timers being off, or some type of frequency scaling problem? -- Michael _______________________________________________ linaro-toolchain mailing list linaro-toolchain@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-toolchain
