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Date:   Tue, 10 Oct 2023 19:15:42 -0700
From:   Stephen Hemminger <stephen@networkplumber.org>
To:     Haiyang Zhang <haiyangz@microsoft.com>
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Subject: Re: [PATCH net-next,v2] tcp: Set pingpong threshold via sysctl
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On Tue, 10 Oct 2023 22:59:49 +0000
Haiyang Zhang <haiyangz@microsoft.com> wrote:

> > > If this an application specific optimization, it should be in a socket option
> > > rather than system wide via sysctl.  
> > Initially I had a similar comment but later decided a sysctl could
> > still be useful if
> > 1) the entire host (e.g. virtual machine) is dedicated to that application
> > 2) that application is difficult to change  
> 
> Yes, the customer actually wants a global setting. But as suggested by Neal,
> I changed it to be per-namespace to match other TCP tunables.

Like congestion control choice, it could be both a sysctl and a socket option.
The reason is that delayed ack is already controlled by socket options.