Re: How to accelerate tcp retransmition

From: Rick Jones
Date: Tue Jan 24 2012 - 12:57:28 EST


On 01/24/2012 06:09 AM, leno soff wrote:
On Tue, Jan 24, 2012 at 4:58 PM, leno soff<lnxuff@xxxxxxxxx> wrote:
Hello everyone,
I have a lot of client, say C1, C2, .. Cn, which route packets to
my servers through router R. But R will drop 70% - 90% _ non-SYN _
packets from clients to Server.

I think you should address that first - why does the router drop 70 to 905 of the non-SYN segments it receives. At first blush that sounds like a classic case of massive over-subscription, and any attempt to accelerate the retransmissions seems destined to trigger congestive collapse.

As a side issue, if the router is dropping 70 to 90% of the non-SYN segments, why is it not also dropping 70 to 90% of the SYN segments?

Also, I'm reasonably confident that an actual keepalive probe would not (or at least should not?) be considered in the three duplicate ACK heuristic.

rick jones
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