Re: GRO: forwading ISATAP packets is very slow with kernel 4.1
On Wed, Jul 15, 2015 at 02:34:41AM +0200, Wolfgang Walter wrote: I wonder if the router may treat all ipv6-tcp connections of a host as a single flow as all those ipv6-packets are embedded in ipv4-packets with the ipv4-address of the host and the ipv4-address of the isatap-gateway and next- header is 41. It may only looks at those? I think GRO is actually working fine. Can you show me the output of ethtool -k eth1? If hardware TSO is enabled can you try disabling it to see if it helps? Thanks, -- Email: Herbert Xu herb...@gondor.apana.org.au Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- 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
Re: GRO: forwading ISATAP packets is very slow with kernel 4.1
Am Mittwoch, 15. Juli 2015, 17:50:20 schrieb Herbert Xu: On Wed, Jul 15, 2015 at 02:34:41AM +0200, Wolfgang Walter wrote: I wonder if the router may treat all ipv6-tcp connections of a host as a single flow as all those ipv6-packets are embedded in ipv4-packets with the ipv4-address of the host and the ipv4-address of the isatap-gateway and next- header is 41. It may only looks at those? I think GRO is actually working fine. Can you show me the output of ethtool -k eth1? If hardware TSO is enabled can you try disabling it to see if it helps? Thanks, Yes. Switching TSO off and leaving GRO on works, too. Thanks, -- Wolfgang Walter Studentenwerk München Anstalt des öffentlichen Rechts -- 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
GRO: forwading ISATAP packets is very slow with kernel 4.1
Hello, I upgraded routers from 3.14.x to 4.1.2. Forwarding ISATAP-packets (IPv4 packets with IPv6 payload) is very slow with 4.1 if GRO is enabled (youtube for example about 64kbit). Disabling GRO on the interfaces restores performance to values comparable to 3.14.x. The kernel is build with IPv6 support but IPv6 is disabled via kernel command line. The router is not a tunnel endpoint, it only forwards the ISATAP- packets. MTU is 1500 on both interfaces. Netfilter conntrack is not used and disabling netfilter has no effect. Regards, -- Wolfgang Walter Studentenwerk München Anstalt des öffentlichen Rechts -- 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
Re: GRO: forwading ISATAP packets is very slow with kernel 4.1
Am Mittwoch, 15. Juli 2015, 08:08:49 schrieben Sie: On Wed, Jul 15, 2015 at 12:16:30AM +0200, Wolfgang Walter wrote: Hello, I upgraded routers from 3.14.x to 4.1.2. Forwarding ISATAP-packets (IPv4 packets with IPv6 payload) is very slow with 4.1 if GRO is enabled (youtube for example about 64kbit). Disabling GRO on the interfaces restores performance to values comparable to 3.14.x. The kernel is build with IPv6 support but IPv6 is disabled via kernel command line. The router is not a tunnel endpoint, it only forwards the ISATAP- packets. MTU is 1500 on both interfaces. Netfilter conntrack is not used and disabling netfilter has no effect. Can you run some tcpdumps and post the results in the two cases? Yes, but I need the cooperation of one of our customers. I wonder if the router may treat all ipv6-tcp connections of a host as a single flow as all those ipv6-packets are embedded in ipv4-packets with the ipv4-address of the host and the ipv4-address of the isatap-gateway and next- header is 41. It may only looks at those? Regards, -- Wolfgang Walter Studentenwerk München Anstalt des öffentlichen Rechts -- 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
Re: GRO: forwading ISATAP packets is very slow with kernel 4.1
On Wed, Jul 15, 2015 at 12:16:30AM +0200, Wolfgang Walter wrote: Hello, I upgraded routers from 3.14.x to 4.1.2. Forwarding ISATAP-packets (IPv4 packets with IPv6 payload) is very slow with 4.1 if GRO is enabled (youtube for example about 64kbit). Disabling GRO on the interfaces restores performance to values comparable to 3.14.x. The kernel is build with IPv6 support but IPv6 is disabled via kernel command line. The router is not a tunnel endpoint, it only forwards the ISATAP- packets. MTU is 1500 on both interfaces. Netfilter conntrack is not used and disabling netfilter has no effect. Can you run some tcpdumps and post the results in the two cases? Thanks, -- Email: Herbert Xu herb...@gondor.apana.org.au Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- 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
