The LTO part runs from 14:00 to 22:00. The streaming seems to only work in Safari (for Macs), but you can download the mp4s in HD (1.2 GB) or SD (300 MB).
They do a good job of describing how it works and why this is kind of a big deal.
I didn't understand fully what it took to achieve this but simply looking at the numbers it is so clear how impressive the work is. Near or better performance with enormously fast build time, significant improvement in incremental compilation and enormous reduction in memory usage. Its unusual to see an optimization attempt succeed from so many different angle.
It's been in the works for quite a while (I remember reading some of the initial RFC postings), although I haven't seen people talk much of it until now. To be fair, I believe this work was primarily done by Google, who also have contributed a lot code to LTO/IPO-based systems in GCC before (such as "Lightweight IPO" or LIPO in GCC) as well as obvious, ongoing Clang/LLVM work. So I imagine they probably had a very good idea of what was necessary to achieve all that... But yes, the results are really impressive!
>How can Apple be shipping it (?) when LLVM is an open source project and it's not in the SVN head yet?
Apple ships their own proprietary forked version of Clang+LLVM, this is for example how they implemented Swift, which was made open source long after it was introduced as part of Apple's proprietary toolchain.
The LTO part runs from 14:00 to 22:00. The streaming seems to only work in Safari (for Macs), but you can download the mp4s in HD (1.2 GB) or SD (300 MB).
They do a good job of describing how it works and why this is kind of a big deal.