From: Tim Chen <[EMAIL PROTECTED]> Date: Tue, 07 Nov 2006 10:32:34 -0800
[ Please bring up networking questions on "netdev@vger.kernel.org" as that is the place where networking developers read bug reports and questions, they by-in-large do not read linux-kernel at all. ] > [TCP]: Send ACKs each 2nd received segment > commit: 1ef9696c909060ccdae3ade245ca88692b49285b > http://kernel.org/git/? > p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1ef9696c909060ccdae3ade245ca88692b49285b > > reduced Volanomark benchmark throughput by 10%. > This is because Volanomark sends > short message (<100 bytes) on its TCP > connections. This patch increases the number of ACKs > traffic by 3.5 times. > > By adopting this patch, we assume that with > small segment, having short delay is important > enough that we are willing to reduce bandwidth > with more ACKs. > > Is there any real application out there > that this new behavior could be a concern? That's unfortunate, because without that patch connections can hang which is more important to fix than your performance test. :-) If we don't ACK every two segments, stacks which grow the congestion window based upon packet counting will not grow the congestion window properly when they are sending smaller than MSS sized segments. This topic has been discussed quite a bit, you may want to do some searching in the netdev archives to read some of that. - 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
