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Date: Wed, 31 May 2023 11:09:54 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Heiner Kallweit <hkallweit1@gmail.com>
Cc: David Miller <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>,
 Paolo Abeni <pabeni@redhat.com>, "netdev@vger.kernel.org"
 <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next] net: don't set sw irq coalescing defaults in
 case of PREEMPT_RT
Message-ID: <20230531110954.6cbf69d1@kernel.org>
In-Reply-To: <87535ce9-4780-d982-0535-d010720aa636@gmail.com>
References: <f9439c7f-c92c-4c2c-703e-110f96d841b7@gmail.com>
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On Wed, 31 May 2023 10:18:40 +0200 Heiner Kallweit wrote:
> > Did someone complain? I don't have an opinion, but I'm curious what
> > prompted the patch.  
> 
> No direct complain, and not covering exactly this point.
> Background: I witnessed some discussions between PREEMPT_RT users
> (e.g. from linuxcnc project) regarding network latency with
> RTL8168 NICs. It seems these users aren't really aware of the
> userspace knobs that the kernel provides for RT optimization.
> To make their life easier we could optimize few things for latency
> and use PREEMPT_RT as an indicator.

Makes sense.