netdev - Re: TCP rx window autotuning harmful at LAN context

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Message-Id: <20090310.091816.178102814.davem@davemloft.net>
Date:	Tue, 10 Mar 2009 09:18:16 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	md@....sk
Cc:	johnwheffner@...il.com, netdev@...r.kernel.org
Subject: Re: TCP rx window autotuning harmful at LAN context

From: Marian Ďurkovič <md@....sk>
Date: Tue, 10 Mar 2009 17:00:40 +0100

> Again, autotuning in its present form removes all safety at the
> receiver side and allows senders to easily bring LANs down. IMHO we
> need to fix this before the problem spreads even more.

There are both global system-wide and socket local limits to how much
memory can be consumed by TCP receive data.  If things get beyond the
configured limits, we back off.  You could modify those if you
personally wish.

It's really good that you brought up this issue.

And it's really good that you've explained your own personal
workaround for this issue.

But it's not good that you want to impose your choosen workaround on
everyone else.