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Date: Thu, 15 Oct 2015 11:13:10 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Christoph Lameter <cl@linux.com>
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Cc: ksummit-discuss@lists.linuxfoundation.org
Subject: Re: [Ksummit-discuss] [TECH TOPIC] Mainlining PREEMPT_RT
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On Thu, 15 Oct 2015 09:22:58 -0500 (CDT)
Christoph Lameter <cl@linux.com> wrote:

> I have no particular use case for my company in mind here. This is what I
> hear when talking to various companies in a number of different areas of
> computing that have tried preempt_rt.

Why are they telling you this and not us? Of course this may be people
that have different requirements.

Need a few microsecond latencies; Try Xenomai.
Need a few hundred microsecond latencies; PREEMPT_RT will do
Need no interference from the kernel; Use NO_HZ_FULL

Look, there's obviously users of PREEMPT_RT, so why are you trying to
kill it? If anything, PREEMPT_RT has made the mainline kernel cleaner.

Just because you don't see a use for it, doesn't mean one does not
exist.

-- Steve