netdev - Re: [PATCH net-next] tcp: auto corking

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Date:	Fri, 06 Dec 2013 10:36:43 -0800
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Rick Jones <rick.jones2@...com>
Cc:	David Laight <David.Laight@...LAB.COM>,
	David Miller <davem@...emloft.net>,
	netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next] tcp: auto corking

On Fri, 2013-12-06 at 10:02 -0800, Rick Jones wrote:

> You mean write, write, read?

Yes, this kind of things. 

"write, write, write, write, < pause or read >, .."


TCP stack tends to increase cwin by insane values in this case.
(one increase per 'line' / ACK)

Just ssh onto a host and look at "ss -emoi src :22" after issuing some
line oriented commands like "ps aux"

I can easily get cwin = 700, while I never sent more than 30KB at once.

If then I send 2MB, they can be sent all at once (and probably trigger
tons of drops)



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