On Jan 9, 2008 9:56 AM, John Heffner <[EMAIL PROTECTED]> wrote: > >> I also wonder how much of a problem this is (for now, with window sizes > >> of order 10000 packets. My understanding is that the biggest problems > >> arise from O(N^2) time for recovery because every ack was expensive. > >> Have current tests shown the final ack to be a major source of problems? > > > > Yes, several people have reported this. > > I may have missed some of this. Does anyone have a link to some recent > data?
I had some testing on this a month ago. A small set of recent results with linux 2.6.23.9 are at http://netsrv.csc.ncsu.edu/net-2.6.23.9/sack_efficiency One of serious cases with a large number of packet losses (initial loss is around 8000 packets) is at http://netsrv.csc.ncsu.edu/net-2.6.23.9/sack_efficiency/600--TCP-TCP-NONE--400-3-1.0--1000-120-0-0-1-1-5-500--1.0-0.5-133000-73-3000000-0.93-150--3/ Also, there is a comparison among three Linux kernels (2.6.13, 2.6.18-rc4, 2.6.20.3) at http://netsrv.csc.ncsu.edu/wiki/index.php/Efficiency_of_SACK_processing Sangtae -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
