+++ Michael Hope [2012-07-18 14:37 +1200]:
The Raspbian project is a rebuild of Debian for the Raspberry Pi. adama did some benchmarks that show the improvement in going from ARMv4T with soft float to ARMv6 with hard float: http://www.memetic.org/raspbian-benchmarking-armel-vs-armhf/
The page says that there's a 4-10 % improvement on integer programs and up to 40 % on floating point programs. It's hard to tell the new instruction vs pipeline influence and if the baseline is soft float or softfp/VFP based.
He said he used debian armel which is soft-float by default, but packages can specify a softfp/vfp build if they wish (I don't know if any do). The tests also don't say anything about controlling for the version of gcc in use. Random binaries in debian armel could have been built with an older gcc than the one used to build rasbian, depending on how long ago they were last uploaded and exactly where he was getting his packages from.
So it's hard to know how much of the improvement is due to compiling for v6 over v4t, soft-float vs vfp, armhf ABI vs armel ABI, and possibly variation in gcc used. I suspect all of those are mixed in.
Interesting nevertheless.
Wookey