RE: [PATCH net-next,v2] tcp: Set pingpong threshold via sysctl

[Haiyang Zhang]

> -----Original Message-----
> From: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
> Sent: Tuesday, October 10, 2023 10:16 PM
> To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> Cc: Yuchung Cheng <ycheng@xxxxxxxxxx>; linux-hyperv@xxxxxxxxxxxxxxx;
> netdev@xxxxxxxxxxxxxxx; KY Srinivasan <kys@xxxxxxxxxxxxx>;
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> mfreemon@xxxxxxxxxxxxxx; mubashirq@xxxxxxxxxx; linux-
> doc@xxxxxxxxxxxxxxx; weiwan@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH net-next,v2] tcp: Set pingpong threshold via sysctl
> 
> On Tue, 10 Oct 2023 22:59:49 +0000
> Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> 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.

I see. I am updating the doc and variable location for this sysctl tunable patch 
as suggested by the reviewers, and will resubmit it.

I will also work on a separate patch for the setsockopt option.

Thanks,
- Haiyang