From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Olsson Subject: Re: Ethernet bridge performance Date: Thu, 7 Aug 2003 21:09:44 +0200 Sender: netdev-bounce@oss.sgi.com Message-ID: <16178.41976.3643.584516@robur.slu.se> References: <3F3217E7.2080903@allot.com> <3F3284EA.5050406@candelatech.com> <3F328A0F.3040005@allot.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: Ben Greear , netdev@oss.sgi.com Return-path: To: Felix Radensky In-Reply-To: <3F328A0F.3040005@allot.com> Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org Felix Radensky writes: > Thanks for your help, Ben. What is skb-recycle patch > and where can I find it ? It's experimental and not updated for almost a year and current implementation does not add anything to SMP. Got some idea how to improve this... but try to keep to slab as long as possible it has been improved. Routing/bridging on SMP has affinty problem. If you are passing skb's say from eth0 to eth1 and they are bound on different CPU's you get cache boucing since the TX-interrupts come on another CPU. In a recent test with pktgen: 300 kpps with TX interrupts on same CPU as sender. 198 kpps with TX intr on different CPU as sender. Recycling tries to address this but current implementation fails as said. But you are probably hit by something else... Check were the drops happens qdisc?. NIC ring RX/TX size, Number of interrupts. ksoftird priority, link HW_FLOW control, checksumming, affinity etc. Cheers. --ro