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Mon, 11 May 2026 05:46:53 -0700 (PDT) Received: from jlelli-thinkpadt14gen4.remote.csb ([151.29.56.132]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-48e6db0b08asm85109005e9.8.2026.05.11.05.46.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 May 2026 05:46:52 -0700 (PDT) Date: Mon, 11 May 2026 14:46:51 +0200 From: Juri Lelli To: Andreas Ziegler Cc: Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: sched/deadline: Use revised wakeup rule for dl_server Message-ID: References: <496e4b3329fe258da9618b9f05b18fcf@umbiko.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <496e4b3329fe258da9618b9f05b18fcf@umbiko.net> Hello, On 08/05/26 08:09, Andreas Ziegler wrote: > Linux kernel version: 6.12 > CONFIG_PREEMPT_RT (w/ PREEMPT_RT patch applied) > Architecture: aarch64 > Platform: Raspberry Pi 4 > > Hi everyone, > > Commit d66792919d4f (sched/deadline: Use revised wakeup rule for dl_server) > [1] introduced a marked degradation in scheduling latency for real-time > tasks in the presence of heavy I/O load. Can this be the same regression reported here? https://marc.info/?l=linux-rt-users&m=177844667227991 Please notice the list of missing subsequent fixes Mike is suggesting to test with. https://marc.info/?l=linux-rt-users&m=177847863710263&w=2 Thanks, Juri