From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt To: Bill Fink Cc: Anton Blanchard , , "David S. Miller" Subject: Re: GigE Performance Comparison of GMAC and SUNGEM Drivers Date: Mon, 19 Nov 2001 13:54:59 +0100 Message-Id: <20011119125459.20923@smtp.adsl.oleane.com> In-Reply-To: <20011119111548.F4531@krispykreme> References: <20011119111548.F4531@krispykreme> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: > > >Hi, > >> The GMAC driver had significantly better performance. It sustained >> 663 Mbps for the 60 second test period, and used 63 % of the CPU on >> the transmitter and 64 % of the CPU on the receiver. By comparison, >> the SUNGEM driver only achieved 588 Mbps, and utilized 100 % of the >> CPU on the transmitter and 86 % of the CPU on the receiver. Thus, >> the SUNGEM driver had an 11.3 % lower network performance while >> using 58.7 % more CPU (and was in fact totally CPU saturated). This is weird and unexpected as GMAC will request interrupt for each transmitted packet while sungem won't However, I noticed that sungem is getting a lot of rxmac and txmac interrupts, I'll investigate this a bit more. (Could you check the difference of /proc/interrupts between a test with gmac and a test with sungem ?) Note that I just updated sungem in my rsync tree, it now has all of the power management and ethtool/miitool support. I plan to replace gmac with sungem completely, so it would be nice to figure out where that problem comes from. Ben. ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/