Hey Derek, Why can't you just change the RSS hash key to whatevery you want it to be via ethtool -X?
Thanks, -Don Skidmore <donald.c.skidm...@intel.com> > -----Original Message----- > From: Derek Ditch [mailto:de...@criticalstack.com] > Sent: Sunday, June 19, 2016 9:20 PM > To: e1000-devel@lists.sourceforge.net > Subject: [E1000-devel] Support for Symmetric RSS Hashing? > > I’ve been using and recommending Intel NICs for years for network sensor > platforms. I’m a huge user of Bro (http://bro.org <http://bro.org/>) and also > leveraged Suricata for signature-based detections. Lately, I’ve started > working > with trying to get away from PF_RING as my hardware interface layer due to > additional complications of out-of-kernel bolt-ons. I’ve really enjoyed the > performance achieved using AF_PACKET for applications that support it. In Bro > (and Suricata and now netsniff-ng), in order to support FANOUT_HASH mode > provided by the kernel, the packets are spread across multiple processes. The > problem is that these applications need symmetric hashing of the connections. > The current ixgbe driver does not provide this guarantee in its RSS hashing. > Recent changes in the kernel further made this a problem by accepting the > hardware calculated hash, when available (for performance reasons, this > would be great, unless you needed symmetric hashing). > > I ran across several discussions where an ixgbe driver was patched to support > this, and also ran across this blog post [1] that used DPDK to override the > driver hash. Can we just update the hash key in the mainline driver so that we > get both good distribution of connections and symmetric hashing? It basically > comes down to swapping out the hash key to ensure the first 32-bits (src ip) > match the second 32-bits (dst ip) and the next 16-bits (src port) match the > following 16-bits (dst port). A published paper provides a key change that > modifies the standard Toeplitz hash function, which does not provide these > guarantees. > > So… Can we just have a better hash function in hardware (via the driver) that > feeds RSS (and now AF_PACKET)? > > Thanks! > > [1] http://galsagie.github.io/2015/02/26/dpdk-tips-1/ > <http://galsagie.github.io/2015/02/26/dpdk-tips-1/> > — > Derek Ditch > de...@criticalstack.com > GPG: 0x2543A3B5 ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports. http://sdm.link/zohomanageengine _______________________________________________ E1000-devel mailing list E1000-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/e1000-devel To learn more about Intel® Ethernet, visit http://communities.intel.com/community/wired
