X-Recipient: archive-cygwin AT delorie DOT com DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3FF513858C52 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com; s=default; t=1693721640; bh=8O6DhZzIcRG+vXAVB7/Uiv+61QSgwN3+U21jP8nKPOE=; h=To:Subject:In-Reply-To:References:Date:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=wvkIUFLllA2A454FOBqUijvjeNsjQHkqYutVVT+6Ansqe6VRzxX14MGfDBarF4rSg BUGB8UuAyIRRjKQeCcUWwZ+/0NbcNvFFiw4kvjgb+hs9fDjEcY/Frz6KIVhLsEaTgQ JsmKdO2CDILknI2kVMC46Tc6vmtqcP5LS+cyXBE0= X-Original-To: cygwin AT cygwin DOT com Delivered-To: cygwin AT cygwin DOT com DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 0642C3858CD1 To: cygwin AT cygwin DOT com Subject: Re: posix thread scaling issue In-Reply-To: <076456ca-2c5d-4bb3-a64b-97ed4bdd26ce@jeffunit.com> (jeff via Cygwin's message of "Sat, 2 Sep 2023 13:04:10 -0700") References: <550e8950-8f7a-4765-b23e-57d0e710fde0 AT jeffunit DOT com> <2cfbcf8d-911f-a64b-8916-12b005c9f6f6 AT Shaw DOT ca> <07386659-68b3-a35d-1402-22684f8e5755 AT Shaw DOT ca> <076456ca-2c5d-4bb3-a64b-97ed4bdd26ce AT jeffunit DOT com> Date: Sun, 03 Sep 2023 08:13:08 +0200 Message-ID: <87h6obss23.fsf@Rainer.invalid> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 X-purgate-type: clean X-purgate: clean X-purgate-size: 1277 X-purgate-ID: 155817::1693721597-76FFBE6D-CFD2C16E/0/0 X-Spam-Status: No, score=-3028.9 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: cygwin AT cygwin DOT com X-Mailman-Version: 2.1.30 Precedence: list List-Id: General Cygwin discussions and problem reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: ASSI via Cygwin Reply-To: ASSI Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com Sender: "Cygwin" jeff via Cygwin writes: > According to the task manager, it says 'Sockets: 1'. That number doesn't matter at all. When you have more than 64 logical processors, you will have processor groups regardless of topology. Below that threshold processor group configuration can be influenced both by BIOS settings and Windows boot parameters. The TL;DR; is that you should configure your box to have a single processor group whenever possible unless your applications either never use enough threads to need more threads than there are in any single group or they are processor group aware. The latter thing means you need to assign each thread that should run on a different processor group than the main program manually to its respective group unless you run on Windows 11 / Windows Server 2022 or later. There is a set of new functions to control that behaviour whose interaction with the old affinity interface and defaults is not very clearly documented. So it seems your best bet would be to either modify your application or upgrade to Win11. Regards, Achim. -- +<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+ SD adaptations for Waldorf Q V3.00R3 and Q+ V3.54R2: http://Synth.Stromeko.net/Downloads.html#WaldorfSDada -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple