On Friday 2010-11-19 13:48, Changli Gao wrote: >On Fri, Nov 19, 2010 at 7:29 PM, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote: >> >> IMHO, the real problem is not the table duplication. We know that adding >> a level of indirection is going to hurt a lot because of cache misses. >> > >Currently, multi-core CPU is common, the cores in a CPU share the >lowest level cache. Duplicate tables use more RAM, and may cause more >pressure of the lowest level cache. There probably should be at most one copy per NUMA node. Maybe less, depending on what the benchmarks will say. I started on some patch to reduce the ruleset from #cpu to #numa_nodes, but then stopped when I ran into the obvious fact that it would require locking the counters because xtables can actually run on more than one core within a given numa node. When decoupling counters from the ruleset, reducing the ruleset copies would become easier. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html