On Thu, 21 Feb 2008 22:24:20 +0100 Ingo Molnar <[EMAIL PROTECTED]> wrote:
> regarding the concept: adaptive mutexes have been talked about in the > past, but their advantage is not at all clear, that's why we havent done > them. It's definitely not an unambigiously win-win concept. When ext3 was converted from sleeping locks to spinlocks, dbench-on-numaq throughput went up by a factor of ten. I'd expect that what RT has done was a truly awful change for lots of workloads on lots of machines. Yeah, there's the dont-enable-it-if-you're-doing-that option, but that adds the we-just-doubled-the-number-of-kernels-distros-need-to-ship problem. Does -rt also make bit_spin_lock preemptible? If not, I'd have thought the change was of little benefit to ext3/jbd and it might as well go back to spinning locks. - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
