On 2/21/07, Ingo Molnar <[EMAIL PROTECTED]> wrote:
I believe this threadlet concept is what user-space will want to use for programmable parallelism.
This is brilliant. Now it needs just four more things: 1) Documentation of what you can and can't do safely from a threadlet, given that it runs in an unknown thread context; 2) Facilities for manipulating pools of threadlets, so you can throttle their concurrency, reprioritize them, and cancel them in bulk, disposing safely of any dynamically allocated memory, synchronization primitives, and so forth that they may be holding; 3) Reworked threadlet scheduling to allow tens of thousands of blocked threadlets to be dispatched efficiently in a controlled, throttled, non-cache-and-MMU-thrashing manner, immediately following the softirq that unblocks the I/O they're waiting on; and 4) AIO vsyscalls whose semantics resemble those of IEEE 754 floating point operations, with a clear distinction between a) pipeline state vs. operands, b) results vs. side effects, and c) coding errors vs. not-a-number results vs. exceptions that cost you a pipeline flush and nonlocal branch. When these four problems are solved (and possibly one or two more that I'm not thinking of), you will have caught up with the state of the art in massively parallel event-driven cooperative multitasking frameworks. This would be a really, really good thing for Linux and its users. Cheers, - Michael - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
