>-----Original Message----- >From: Scott Silverman [mailto:[email protected]] >Sent: Wednesday, April 03, 2013 10:45 AM >To: [email protected] >Subject: [E1000-devel] Issues using ioatdma / DCA > >I'm trying to get the linux networking stack to start using ioatdma (and, >ideally, DCA as well). > >Despite my efforts, the "/sys/class/dma/dma*chan*/in_use" is never set to >1, and the memcpy_count and bytes_transferred stay at 0. > >I'm working with two systems, one using igb, and the other using ixgbe, I >have the same results with both. I've tried the in-kernel igb driver (for >82576), as well as the three most recent ixgbe drivers (for 82599EB), same >results (though sometimes "in_use" is 5, or 8, instead of 2). > >What am I missing?
By default only very large packets will go through ioatdma. You can control this by setting: sysctl net.ipv4.tcp_dma_copybreak=<packet size> if you set it very low (like 1) you should see the byte counter incrementing when receiving TCP packets. Thanks, Emil ------------------------------------------------------------------------------ Minimize network downtime and maximize team effectiveness. Reduce network management and security costs.Learn how to hire the most talented Cisco Certified professionals. Visit the Employer Resources Portal http://www.cisco.com/web/learning/employer_resources/index.html _______________________________________________ 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
