See this link: http://timetobleed.com/enabling-bios-options-on-a-live-server-with-no-rebooting/
It explains how to set the DMA in BIOS even in cases where: * some BIOSes don’t expose a way to turn DCA on even though it is supported by the CPU, chipset, and NIC! * Your hosting provider may not allow BIOS access * Your system might be up and running and you don’t want to reboot to enter the BIOS to enable DCA On Thu, Jul 15, 2010 at 8:28 AM, "Brandeburg, Jesse" <[email protected]> wrote: > 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 > ------------------------------------------------------------------------------ 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
