From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <395B9171.76934B4E@netx4.com> Date: Thu, 29 Jun 2000 14:12:01 -0400 From: Dan Malek MIME-Version: 1.0 To: Graham Stoney CC: LinuxPPC Embedded Mailing List Subject: Re: FEC performance on the 855T/860T References: <20000629120913.8045B5060C@brixi.research.canon.com.au> Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Graham Stoney wrote: > .....The first bottleneck to stand > out is that the FEC port isn't going as fast as we'd like. We have discussed this before. The FEC runs at 100 Mbits/sec, back to back packets. It has to....there isn't any buffer space in the FEC to do otherwise. The bottleneck is the protocol and application processing in the PPC core. The performance of a TCP/IP connection scales nearly linearly with the processor speed. The 50 MHz 860P will run about 30 Mbits/sec TCP/IP, and a 100 MHz 860P will run about 60 Mbits/sec TCP/IP. You can write a program that will send back-to-back Ethernet frames at the maximum rate, and will read and discard Ethernet frames at the maximum rate. Just write a program (nttcp works) to benchmark using the local loopback device. That will tell you what the processor can accomplish. -- Dan ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/