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Date: Mon, 10 Feb 2025 14:44:32 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: David Laight <david.laight.linux@gmail.com>
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Subject: Re: [RFC][PATCH 1/2] sched: Extended scheduler time slice
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On Mon, 10 Feb 2025 12:27:00 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Mon, 10 Feb 2025 17:20:59 +0000
> David Laight <david.laight.linux@gmail.com> wrote:
> 
> > Hmmm... you lose big-time anyway.
> > 
> > All you need is a lot of network traffic 'pinch' the process context until
> > the hardware interrupt, NAPI softint code and rcu softint code completes.
> > That can easily take several milliseconds.  
> 
> Not on PREEMPT_RT. All that runs as threads.
> 
> And this is a feature that we would like on RT for non RT tasks.

Actually, this doesn't even need PREEMPT_RT to not hit your example. You
can build and boot your system with interrupts as threads, and that also
includes softirqs.

-- Steve