Date: Fri, 14 May 2004 14:44:54 -0400 From: John Baldwin <jhb@FreeBSD.org> To: freebsd-current@FreeBSD.org Cc: Gerrit Nagelhout <gnagelhout@sandvine.com> Subject: Re: 4.7 vs 5.2.1 SMP/UP bridging performance Message-ID: <200405141444.54385.jhb@FreeBSD.org> In-Reply-To: <FE045D4D9F7AED4CBFF1B3B813C85337021AB372@mail.sandvine.com> References: <FE045D4D9F7AED4CBFF1B3B813C85337021AB372@mail.sandvine.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tuesday 04 May 2004 03:55 pm, Gerrit Nagelhout wrote: > Hi, > > For one of our applications in our testlab, we are running bridge(4) > with several user land applications. I have found that the bridging > performance (64 byte packets, 2-port bridge) on 5.2.1 is > significantly lower than that of RELENG_4, especially when running in > SMP. The platform is a dual 2.8GHz xeon with a dual port em (100MHz > PCI-X). Invariants are disabled, and polling (with idle_polling > enabled) is used. Well, I do have a patch you can try but I am unsure if it will help or not. Basically, the new interrupt code in 5.2 has a bug that can really hurt interrupt latency when doing kernel-intensive tasks. Since you are using polling it may not help much, but it's still something you can try. The patch should apply to 5.2.1 just fine. http://www.FreeBSD.org/~jhb/patches/ithread_preempt.patch -- John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200405141444.54385.jhb>