lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-Id: <1271938343.4032.30.camel@bigi> Date: Thu, 22 Apr 2010 08:12:23 -0400 From: jamal <hadi@...erus.ca> To: Eric Dumazet <eric.dumazet@...il.com> Cc: Changli Gao <xiaosuo@...il.com>, Rick Jones <rick.jones2@...com>, David Miller <davem@...emloft.net>, therbert@...gle.com, netdev@...r.kernel.org, robert@...julf.net, andi@...stfloor.org Subject: Re: rps perfomance WAS(Re: rps: question On Wed, 2010-04-21 at 21:01 +0200, Eric Dumazet wrote: > Drawback of using a fixed src ip from your generator is that all flows > share the same struct dst entry on SUT. This might explain some glitches > you noticed (ip_route_input + ip_rcv at high level on slave/application > cpus) yes, that would explain it ;-> I could have flows going to each cpu generating different unique dst. It is good i didnt ;-> > Also note your test is one way. If some data was replied we would see > much use of the 'flows' > In my next step i wanted to "route" these packets at app level and for this stage of testing just wanted to sink the data to reduce experiment variables. Reason: The netdev structure would hit a lot of cache misses if i started using it to both send/recv since lots of things are shared on tx/rx (example napi tx prunning could happen on either tx or receive path); same thing with qdisc path which is at netdev granularity.. I think there may be room for interesting improvements in this area.. > I notice epoll_ctl() used a lot, are you re-arming epoll each time you > receive a datagram ? I am using default libevent on debian. It looks very old and maybe buggy. I will try to upgrade first and if still see the same investigate. > I see slave/application cpus hit _raw_spin_lock_irqsave() and > _raw_spin_unlock_irqrestore(). > > Maybe a ring buffer could help (instead of a double linked queue) for > backlog, or the double queue trick, if Changli wants to respin his > patch. > Ok, I will have some cycles later today/tommorow or for sure on weekend. My setup is still intact - so i can test. cheers, jamal -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists