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Subject: RE: [PATCH 1/1] tcp: Wrong timeout for SYN segments
From: Eric Dumazet <eric.dumazet@gmail.com>
To: David Laight <David.Laight@ACULAB.COM>
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Date: Thu, 23 Aug 2012 14:51:23 +0200
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On Thu, 2012-08-23 at 13:35 +0100, David Laight wrote:
> > I would suggest to increase TCP_SYN_RETRIES from 5 to 6.
> > 
> > 180 secs is eternity, but 31 secs is too small.
> 
> Wasn't the intention of the long delay to allow a system
> acting as a router to reboot?
> I suspect that is why it (and some other TCP timers)
> are in minutes.

One could argue that if an application really wants to connect to a
peer, it should probably handle failures and retries.

But for unaware (basic ?) applications, the 3 -> 1 change reduced by a 3
factor the timeout. So a transient network failure has now more
chance to impact them.

Not all applications run inside a browser or under human control...