From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David S. Miller" Subject: Re: e1000 performance hack for ppc64 (Power4) Date: Fri, 13 Jun 2003 16:52:50 -0700 (PDT) Sender: netdev-bounce@oss.sgi.com Message-ID: <20030613.165250.41635765.davem@redhat.com> References: Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: anton@samba.org, haveblue@us.ibm.com, hdierks@us.ibm.com, dwg@au1.ibm.com, linux-kernel@vger.kernel.org, milliner@us.ibm.com, ricardoz@us.ibm.com, twichell@us.ibm.com, netdev@oss.sgi.com Return-path: To: scott.feldman@intel.com In-Reply-To: Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org From: "Feldman, Scott" Date: Fri, 13 Jun 2003 16:52:18 -0700 > > Why not instead find out if it's possible to have the e1000 > > fetch the entire cache line where the first byte of the > > packet resides? Even ancient designes like SunHME do that. > > Rusty and I were wondering why the e1000 didnt do that exact thing. > > Scott: is it possible to enable such a thing? I thought the answer was no, so I double checked with a couple of hardware guys, and the answer is still no. Sigh... So Anton, when the PCI controller gets a set of sub-cacheline word reads from the device, it reads the value from memory once for every one of those words? ROFL, if so... I can't believe they wouldn't put caches on the PCI controller for this, at least a one-behind that snoops the bus :(