Yes, I think that's the issue. With our 20ms timeslots it was taking too long to do a bunch of reads so we added an ioctl to the tap driver to read a bunch of packets into a buffer. I think we can remove the rtnl lock for this particular ioctl. We didn't see an issue with the e1000 motherboard interface, but maybe that one just releases the lock faster..
Thanks a bunch, Aaron On Wed, Mar 26, 2014 at 10:51 AM, Rustad, Mark D <[email protected]> wrote: > On Mar 26, 2014, at 10:24 AM, Aaron Brice <[email protected]> wrote: > >> On Tue, Mar 25, 2014 at 10:39 PM, Ronciak, John <[email protected]> >> wrote: >>> How are the different PCIe slots connected into the system? In a lot of >>> cases some of the slots are not all equal in terms of how they are laid out >>> in the system. If you move the interface doing the 20ms read to a NIC in a >>> different slot does the behavior change? Does the i/f on the m/b if used >>> for the 20ms read work correctly? >> >> The odd part is that the process doing the 20ms read is reading from a >> virtual tap interface (/dev/net/tun) and not from one of the NICs. It >> seems like bringing down the igb interface is causing some system >> level lock at least for network I/O? >> >> Aaron > > That sounds like the rtnl lock to me. Are you doing ioctls on the tap > interface at that time? I believe that the ioctls will take the rtnl lock, > which is likely to delay things for you. > > -- > Mark Rustad, Networking Division, Intel Corporation > ------------------------------------------------------------------------------ Learn Graph Databases - Download FREE O'Reilly Book "Graph Databases" is the definitive new guide to graph databases and their applications. Written by three acclaimed leaders in the field, this first edition is now available. Download your free book today! http://p.sf.net/sfu/13534_NeoTech _______________________________________________ E1000-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/e1000-devel To learn more about Intel® Ethernet, visit http://communities.intel.com/community/wired
