From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 8 Mar 2002 09:03:41 +0100 From: Harald Welte To: "Ruhland, Paul" Cc: "'linuxppc-dev@lists.linuxppc.org'" Subject: Re: Ethernet, kernel bug/weakness Message-ID: <20020308090341.V6936@sunbeam.de.gnumonks.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: ; from PRuhland@microwavedata.com on Thu, Mar 07, 2002 at 03:50:04PM -0500 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Thu, Mar 07, 2002 at 03:50:04PM -0500, Ruhland, Paul wrote: > Effect: > -- > Once the ethernet traffic goes above the critical point described above, all > cpu cycles are spent servicing the ethernet traffic. This is a common problem, also found with gigabit ethernet and large x86 boxes (or 100MBit and medium x86 boxes), as soon as you start shooting at them with foll wire speed 20bytes IP packets. It is well-known and about two years ago Jamal Hadi Selim and others were solving the problem for a couple of example ethernet chips by using IRQ mitigation. This way the packets will get dropped on the network card itself. Seems like your driver isn't using this strategy for some strange reason. Alternatively you can also try to detect high load within the driver and switch to polling mode - this also has been implemented successfully in some drivers, IIRC. > Paul Ruhland -- Live long and prosper - Harald Welte / laforge@gnumonks.org http://www.gnumonks.org/ ============================================================================ GCS/E/IT d- s-: a-- C+++ UL++++$ P+++ L++++$ E--- W- N++ o? K- w--- O- M+ V-- PS++ PE-- Y++ PGP++ t+ 5-- !X !R tv-- b+++ !DI !D G+ e* h--- r++ y+(*) ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/