On Thu, 2010-07-15 at 02:45 -0700, Ali Gholami Rudi wrote: > Hi, > > Trying to find out why 82598 is dropping packets (rx_missed_errors) > while the cpus are only 30% utilized (using 8-queues), I realized > that DCA is disabled; that is (adapter->flags & IXGBE_FLAG_DCA_ENABLED) > is false while the kernel has been compiled with IXGBE_DCA and > INTEL_IOATDMA marked as builtins.
okay, thats a good start. > Inspecting the code showed that dca_add_requester() in ixgbe_probe() > fails with -ENODEV and in dca_add_requester(), dca_find_domain() > returns NULL. I tried the card on HP DL380G6 and BL460cG6 with > the same result. Is there something I'm missing? Also could it > be related to packet drops? I believe that the HP systems don't come with DCA enabled in the BIOS, and I'm not sure about this but I think that they don't allow it to be enabled in the BIOS. As to why that might be you'll have to ask HP, sorry. We are aware that some vendors do not turn on DCA. This is why the ioatdma/dca combo won't allow you to register with ioatdma, because the MSR registers in the chipset/processor are not showing DCA capability is enabled. Hope this helps, Jesse ------------------------------------------------------------------------------ This SF.net email is sponsored by Sprint What will you do first with EVO, the first 4G phone? Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first _______________________________________________ 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
