From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <3CD9425D.2020206@embeddededge.com> Date: Wed, 08 May 2002 11:21:01 -0400 From: Dan Malek MIME-Version: 1.0 To: acurtis@onz.com Cc: linuxppc-dev@lists.linuxppc.org Subject: Re: 8260 and skb implementation References: Content-Type: text/plain; charset=us-ascii; format=flowed Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: Allen Curtis wrote: >>...I don't think SK bufs will because of the high processor core access. > > > I am not sure what you are saying here? The advantage of the local RAM is for the CPM to better satisfy its memory resource requirements by not having to compete with the PowerPC core (or other bus masters) for 60x bus access. Since the SK buffers are predominantly used by the PowerPC core during its IP stack and application processing, I doubt there is any performance benefit. However, it isn't hard to cause SK buffers to be allocated from this memory for testing purposes, and I would run some benchmarks that represent your application rather than design by speculation :-) > You would think that alignment was a common implementation concern. It's a concern, but we are lucky they are aligned properly. The transmit buffers are 16-bit aligned due to the way the headers are built, which causes trouble for some controllers. -- Dan ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/