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[151.18.214.147]) by smtp.gmail.com with ESMTPSA id f6sm2630914wme.32.2020.09.08.22.51.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Sep 2020 22:51:06 -0700 (PDT) Date: Wed, 9 Sep 2020 07:51:03 +0200 From: Juri Lelli To: Pavel Machek Cc: peterz@infradead.org, mingo@redhat.com, rostedt@goodmis.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it, tommaso.cucinotta@santannapisa.it, alessio.balsini@gmail.com, bristot@redhat.com, dietmar.eggemann@arm.com, linux-rt-users@vger.kernel.org, mtosatti@redhat.com, williams@redhat.com, valentin.schneider@arm.com Subject: Re: [RFC PATCH v2 0/6] SCHED_DEADLINE server infrastructure Message-ID: <20200909055103.GA18215@localhost.localdomain> References: <20200807095051.385985-1-juri.lelli@redhat.com> <20200908222252.GC1005@bug> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200908222252.GC1005@bug> Sender: linux-rt-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org Hi Pavel, On 09/09/20 00:22, Pavel Machek wrote: > Hi! > > > This is RFC v2 of Peter's SCHED_DEADLINE server infrastructure > > implementation [1]. > > > > SCHED_DEADLINE servers can help fixing starvation issues of low priority tasks (e.g., > > SCHED_OTHER) when higher priority tasks monopolize CPU cycles. Today we have RT > > Throttling; DEADLINE servers should be able to replace and improve that. > > It would be worth noting what "server" is in this context. It comes from Constant Bandwidth Server (CBS), that SCHED_DEADLINE is implementing [1]. > > It is not white box with CPU inside, it is not even an userland process, afaict. > > Subject is quite confusing. Best, Juri 1 - https://elixir.bootlin.com/linux/latest/source/Documentation/scheduler/sched-deadline.rst#L42