[PATCH] Add a new TCP_IGNOREIDLE socket option

[Andre Oppermann]

On 10.02.2013 11:36, Andrey Zonov wrote:
> On 2/10/13 9:05 AM, Kevin Oberman wrote:
>>
>> This is a subject rather near to my heart, having fought battles with
>> congestion back in the dark days of Windows when it essentially
>> defaulted to TCPIGNOREIDLE. It was a huge pain, but it was the only
>> way Windows did TCP in the early days. It simply did not implement
>> slow-start. This was really evil, but in the days when lots of links
>> were 56K and T-1 was mostly used for network core links, the Internet,
>> small as it was back then, did not melt, though it glowed a
>> frightening shade of red fairly often. Today too many systems running
>> like this would melt thins very quickly.
>>
>
> Google made many many TCP tweaks.  Increased initial window, small RTO,
> enabled ignore after idle and others.  They published that, other people
> just blindly applied these tunings and the Internet still works.

In general Google does provide quite a bit of data with their experiments
showing that it isn't harmful and that it helps the case.

Smaller RTO (1s) has become a RFC so there was very broad consensus in
TCPM that is a good thing.  We don't have it yet because we were not fully
compliant in one case (loss of first segment).  I've fixed that a while
back and will bring 1s RTO soon to HEAD.

I'm pretty sure that Google doesn't ignore idle on their Internet facing
servers.  They may have proposed a decay mechanism in the past.  I'd have
to check the TCPM archives for that.

-- 
Andre