v1 -> v2: - Move the /128 route bug fixes to another series (posted). - Create a function for checking (rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY)). - Avoid shuffling the skb network_header. Instead, change the function signature to take iph instead of skb.
The perf numbers do not change much since v1. It depends on another patch series, 'ipv6: Stop /128 route from disappearing after pmtu update', which should be applied first. Many thanks to "Hannes Frederic Sowa <han...@stressinduktion.org>" on reviewing the patches and giving advice. --Martin ~~~ start: v1 compose message (with the out-dated parts removed) ~~~ This series is to avoid creating a RTF_CACHE route whenever we are consulting the fib6 tree with a new destination. Instead, only create RTF_CACHE route when we see a pmtu exception. Out of all ipv6 RTF_CACHE routes that are created, the percentage that has a different mtu is very small. In one of our end-user facing proxy server, only 1k out of 80k RTF_CACHE routes have a smaller MTU. For our DC traffic, there is no mtu exception. A large fib6 tree has problems like, 'ip -6 r show' takes a long time. gc may kick in too often. Also, when a service has restarted and a lot of new TCP conn requests come in, it creates pressure on the tree by inserting a lot of RTF_CACHE in a short time and it currently requires a write lock to do that. The first few patches are prep works to remove assumption that the returned rt is always RTF_CACHE. The patch 'ipv6: Only create RTF_CACHE routes after encountering pmtu exception' do the lazy RTF_CACHE route creation. The following patches added percpu rt to compensate the performance loss after doing the RTF_CACHE lazy creation. Here is some numbers of the udpflood test. The udpflood has been slightly modified to have a time limit instead of count limit. A /64 via gateway route is used for the test. Each udpflood uses 10000 dst addresses. The dst addresses of different udpflood processes do not overlap with each other. # of udpflood # of trans (patched) # of trans (upstream) 1 16M 15M 10 61M 61M 20 65M 62M 40 88M 83M ~~~ end: v1 compose message ~~~ -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
