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Date: Wed, 30 Jan 2013 12:11:23 -0500
From: Alfred Perlstein <bright@mu.org>
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To: John Baldwin <jhb@freebsd.org>
Subject: Re: [PATCH] Add a new TCP_IGNOREIDLE socket option
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Cc: Sepherosa Ziehau <sepherosa@gmail.com>, freebsd-net@freebsd.org,
 Bjoern Zeeb <bz@freebsd.org>, Andre Oppermann <andre@freebsd.org>
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On 1/30/13 11:58 AM, John Baldwin wrote:
> On Tuesday, January 29, 2013 6:07:22 pm Andre Oppermann wrote:
>>
>> Yes, unfortunately I do object.  This option, combined with the inflated
>> CWND at the end of a burst, effectively removes much, if not all, of the
>> congestion control mechanisms originally put in place to allow multiple
>> [TCP] streams co-exist on the same pipe.  Not having any decay or timeout
>> makes it even worse by doing this burst after an arbitrary amount of time
>> when network conditions and the congestion situation have certainly changed.
> You have completely ignored the fact that Linux has had this as a global
> option for years and the Internet has not melted.  A socket option is far more
> fine-grained than their tunable (and requires code changes, not something a
> random sysadmin can just toggle as "tuning").

I agree with John here.

While Andre's objection makes sense, since the majority of Linux/Unix 
hosts now have this as a global option I can't think of why you would 
force FreeBSD to be a final holdout.

-Alfred