Can anyone speak to just how much real-world performance is actually lost due to Debian not being natively compiled for ARMv6 (like the Fedora remix is?)
Aargh. From a bit of reading at Debian''s website, it looks like it could be quite a bad performance loss (at least whenever one is doing anything that heavily relies on floating point operations):
"Genesi USA, Inc. did a proof-of-concept rebuild of Ubuntu karmic (9.10)'s armel port with the hard-floating. They noticed important wins (in the order of 40% performance improvement) in floating-point heavy applications/libraries such as mesa, with a Cortex-A8 CPU."
Note: The Cortex-A8 mentioned above is ARMv7, whereas the Raspberry Pi is only ARMv6. So that''s not an apples-to-apples comparison. I''m still awaiting to see a fair comparison of hardfloat-vs-no-hardfloat on the Raspberry Pi's ARMv6.
So what hope is there of Debian officially compiling hardfloat support for the RasPi?
It would seem none, at the moment. Maybe we should all petition them to include it? We''d have to act fast, before Debian's upcoming freeze occurs "sometime in the middle of 2012".
The current situation seems to go something like this: Even though the Raspberry Pi''s ARMv6 processor has "hardware floating point" (the CPU feature is called "VFP"), Debian''s current, official "ARM EABI" port (for Debian 6) unfortunately does not compile support for VFP in!
In other words, once all the new Rasberry Pi users install Debian for the first time, as it currently stands, they might be disappointed to discover that their floating point hardware functionality just sits there, affectively unusable. All floating point operations (think "Multimedia") will instead be done using software-based emulation, incurring a substantial loss in performance. Am I right on this?
To make matters worse, Debian is cooking up a new official port for the ARM, called "ArmHardFloatPoint", which they hope to officially include in Debian 7. But it will only cover ARMv7 (which have VFP), and above (think BeagleBone). So, as it stands, the Raspberry Pi will "miss the boat," since it's only ARMv6.
Failing convincing Debian to officially include support for the Raspberry Pi's hardware floating point in Debian 7, the only other option will be to make an "unofficial" port (akin to how there is a "Remix" of Fedora for the Raspberry Pi. This would necessitate a group of avid Raspberry Pi fans making (or getting access to) their own build cluster (like Seneca College did), and rebuilding all the Debian packages, compiling for the ARMv6 with hardware float support. Then they would also have to make their own package repositories, security update packages (in a timely, consistent manner), website, etc. That might be a lot of work!
Any corrections or additions to the above would be most appreciated.
In summary: perhaps I''ll just think twice about using some different compile-optimized distro on the Raspberry Pi, after all. I''m starting to warm up to Puppy, since it's been painstakingly designed specifically to run nicely in 256 MB RAM (for a long time now).