So far i've just watched the 'programmer' keynote from Phil - it's a pity about the emphasis on C++ which is such a shit language - but what are you gonna do eh? His talk on the viola-jones haar cascade algorithm was interesting, how HSA could be used to split up algorithms to move the problem to where it is most efficiently solved (not sure how it compares to face-detector in socles, as I solved the problem of idle work-items in a different way). But yeah, looking forward to that capability in the future; during my last visit to OpenCL in the last month or so I kept thinking that being able to run stuff on the CPU where it made sense would ... make sense.
I slightly disagree that the problem with the GPU parallel programming is just that it is too hard to write - all good software is hard to write - I think it more has to do with the availability of the platform. e.g. PS3 is hard to write too, but there seems to be plenty of that now because everyone's writing to the same platform. If I was a commercial developer writing software, right now it's only going to be a niche (photoshop is a niche). This is ok - because niche customers are probably already using capable hardware or don't mind buying it - but for mass market adoption it requires mass market availability of stable, quality, compatible platforms. This is still some way off.
The videos are on the summit broadcast site which requires a freely available login.
Update: Blah, ahh well, mostly a bit dull & sparse this year, or maybe they just weren't all put up on the net. The HSA stuff is the most interesting again from a software perspective.
Update 2: Apparently more content will be added over time, I guess last year I didn't spot it for a few months so had a lot more to look at off the bat.
On more reflection the HSA foundation and the HSAIL stuff is pretty big news. People don't seem to understand why it's so important though. It's really about the H in HSA - heterogeneous. Being able to support many CPUs with the same code and even the same compiler. Being able to target the code at run-time to execute on the most efficient hardware available in the current system. And being able to do that in a practical way that isn't tied to some vendor-specific secret sauce using broken proprietary compilers. At the bottom of it, it's just another attempt at 'write once, run everywhere' technology, but this time for computationally intensive processing and not for desktop user applications. I guess time will tell to see how it goes without nvidia and intel though. And the same as to whether this finally allows free software to take part.
The other part of it is coming up with a set of re-usable libraries so that the performance is opened up to non-gun-hackers (or in their terms, non-'ninja'-programmers), although TBH I don't see that is any different to any other modern hierarchical programming environment full of frame-works and tool-kits. This can already be done with OpenCL anyway, but I suppose there is still messy crap to deal with from the idiot-programmer's perspective. e.g separate memory spaces, device-host copy overheads and so on. HSA with code transparently intermingling with plain old host code means the same could be done without the overheads and make it more attractive.
I still think the biggest hurdle for application developers is platform support. Any extra work has to be justifiable if it is only going to benefit a part of your customer base.
Update: I never got around to seeing the actual talks at the time but I just found that Stream Computing have a nice index of all the OpenCL specific talks. I'm not a regular reader of their blog but every now and then I do a search in which it turns up and I do a catch up ...
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