Re: [RFC PATCH 00/30] Kernel NET policy

From: Florian Westphal
Date: Mon Jul 18 2016 - 12:17:47 EST

Liang, Kan <kan.liang@xxxxxxxxx> wrote:
> > What is missing in the kernel UAPI so userspace could do these settings on its
> > own, without adding this policy stuff to the kernel?
> The main purpose of the proposal is to simplify the configuration. Too many
> options will let them confuse.
> For normal users, they just need to tell the kernel that they want high throughput
> for the application. The kernel will take care of the rest.
> So, I don't think we need an interface for user to set their own policy settings.

I don't (yet) agree that the kernel is the right place for this.
I agree that current (bare) kernel config interface(s) for this are
hard to use.

> > It seems strange to me to add such policies to the kernel.
> But kernel is the only place which can merge all user's requests.

I don't think so.

If different requests conflict in a way that is possible to do something
meaningful the I don't see why userspace tool cannot do the same

> > Addmittingly, documentation of some settings is non-existent and one needs
> > various different tools to set this (sysctl, procfs, sysfs, ethtool, etc).
> >
> > But all of these details could be hidden from user.
> > Have you looked at tuna for instance?
> Not yet. Is there similar settings for network?

Last time I checked tuna could only set a few network-related sysctls
and handle irq settings/affinity, but not e.g. tune irq coalescening
or any other network interface specific settings.