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[209.85.218.50]) by smtp.gmail.com with ESMTPSA id q17-20020a1709060e5100b00a4623030893sm7819211eji.126.2024.04.03.09.56.44 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 03 Apr 2024 09:56:44 -0700 (PDT) Received: by mail-ej1-f50.google.com with SMTP id a640c23a62f3a-a4e61accceaso11927666b.2 for ; Wed, 03 Apr 2024 09:56:44 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCU0LPvw7yitGO79DwtBCUKIE3GNaT0xAQk8RTPgUJa8z015dX6dV5FxswjehAim8qo6OmEnuMrgtCbx1RyM2ScsMDikZR2XxO8tuvcV X-Received: by 2002:a17:906:3945:b0:a4e:6b94:7d4 with SMTP id g5-20020a170906394500b00a4e6b9407d4mr6495526eje.24.1712163403638; Wed, 03 Apr 2024 09:56:43 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <969ccc0f-d909-4b45-908e-e98279777733@metaparadigm.com> In-Reply-To: <969ccc0f-d909-4b45-908e-e98279777733@metaparadigm.com> From: Linus Torvalds Date: Wed, 3 Apr 2024 09:56:27 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: user-space concurrent pipe buffer scheduler interactions To: Michael Clark Cc: Jens Axboe , Ingo Molnar , Peter Zijlstra , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" On Tue, 2 Apr 2024 at 13:54, Michael Clark wrote: > > I am working on a low latency cross-platform concurrent pipe buffer > using C11 threads and atomics. You will never get good performance doing spinlocks in user space unless you actually tell the scheduler about the spinlocks, and have some way to actually sleep on contention. Which I don't see you as having. Linus