Date: Tue, 7 Apr 2009 12:57:48 +0800 From: Sepherosa Ziehau <sepherosa@gmail.com> To: Ivan Voras <ivoras@freebsd.org> Cc: freebsd-net@freebsd.org Subject: Re: Advice on a multithreaded netisr patch? Message-ID: <ea7b9c170904062157u1c457f27md565f9a95a51a705@mail.gmail.com> In-Reply-To: <grac1s$p56$1@ger.gmane.org> References: <gra7mq$ei8$1@ger.gmane.org> <alpine.BSF.2.00.0904051422280.12639@fledge.watson.org> <grac1s$p56$1@ger.gmane.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, Apr 5, 2009 at 9:34 PM, Ivan Voras <ivoras@freebsd.org> wrote: > Robert Watson wrote: >> >> On Sun, 5 Apr 2009, Ivan Voras wrote: >> >>> I thought this has something to deal with NIC moderation (em) but >>> can't really explain it. The bad performance part (not the jump) is >>> also visible over the loopback interface. >> >> FYI, if you want high performance, you really want a card supporting >> multiple input queues -- igb, cxgb, mxge, etc. if_em-only cards are PCI-E em(4) supports 2 RX queues. 82571/82572 support 2 TX queues. I have not tested multi-TX queues, but em(4) multi-RX queues work well in dfly (tested with 82573 and 82571) >> fundamentally less scalable in an SMP environment because they require >> input or output to occur only from one CPU at a time. > > Makes sense, but on the other hand - I see people are routing at least > 250,000 packets per seconds per direction with these cards, so they > probably aren't the bottleneck (pro/1000 pt on pci-e). It should be some variants of 82571EB Best Regards, sephe -- Live Free or Die
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?ea7b9c170904062157u1c457f27md565f9a95a51a705>