On 3/2/07, Eric Dumazet <[EMAIL PROTECTED]> wrote:
Thank you for this report. (Still avoiding cache misses studies, while they obviously are the limiting factor)
1) The entire point of going to a tree-like structure would be to allow the leaves to age out of cache (or even forcibly evict them) when the structure bloats (generally under DDoS attack), on the theory that most of them are bogus and won't be referenced again. It's not about the speed of the data structure -- it's about managing its impact on the rest of the system. 2) The other entire point of going to a tree-like structure is that they're drastically simpler to RCU than hashes, and more generally they don't involve individual atomic operations (RCU reaping passes, resizing, etc.) that cause big latency hiccups and evict a bunch of other stuff from cache. 3) The third entire point of going to a tree-like structure is to have a richer set of efficient operations, since you can give them a second "priority"-type index and have "pluck-highest-priority-item", three-sided search, and bulk delete operations. These aren't that much harder to RCU than the basic modify-existing-node operation. Now can we give these idiotic micro-benchmarks a rest until Robert's implementation is tuned and ready for stress-testing? Cheers, - Michael - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
