Comcast sends packets OOO. With any decent number of internet hops you're likely to encounter a load balancer or packet shaper that sends packets OOO, so you just can't be worried about it. In fact, your designs MUST work with OOO packets.
Getting balance on your load balanced lines is certainly a bigger upside than the additional CPU used. You can buy a faster processor for your "stack" for a lot less than you can buy bandwidth. Frankly my opinion of LRO is that it's a science project suitable for labs only. It's a trick to get more bandwidth than your bus capacity; the answer is to not run PCIe2 if you need pcie3. You can use it internally if you have control of all of the machines. When I modify a driver the first thing that I do is rip it out. BC ________________________________ From: Luigi Rizzo <ri...@iet.unipi.it> To: Barney Cordoba <barney_cord...@yahoo.com> Cc: Andre Oppermann <an...@freebsd.org>; Alan Somers <asom...@freebsd.org>; "n...@freebsd.org" <n...@freebsd.org>; Jack F Vogel <j...@freebsd.org>; Justin T. Gibbs <gi...@freebsd.org>; T.C. Gubatayao <tgubata...@barracuda.com> Sent: Saturday, August 31, 2013 10:27 PM Subject: Re: Flow ID, LACP, and igb On Sun, Sep 1, 2013 at 4:15 AM, Barney Cordoba <barney_cord...@yahoo.com>wrote: > ... > [your point on testing with realistic assumptions is surely a valid one] > > Of course there's nothing really wrong with OOO packets. We had this > discussion before; lots of people > have round robin dual homing without any ill effects. It's just not an > issue. > It depends on where you are. It may not be an issue if the reordering is not large enough to trigger retransmissions, but even then it is annoying as it causes more work in the endpoint -- it prevents LRO from working, and even on the host stack it takes more work to sort where an out of order segment goes than appending an in-order one to the socket buffer. cheers luigi _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org" _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
