From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mr6.vodafonemail.de (mr6.vodafonemail.de [145.253.228.166]) by sourceware.org (Postfix) with ESMTPS id 0642C3858CD1 for ; Sun, 3 Sep 2023 06:13:23 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 0642C3858CD1 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=nexgo.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=nexgo.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nexgo.de; s=vfde-smtpout-mb-15sep; t=1693721601; bh=w+3LLk6GvODX1eSiTpg4MUb4/b1yWYAYPzzBrXXDISw=; h=From:To:Subject:In-Reply-To:References:Date:Message-ID:User-Agent: Content-Type:From; b=Olxp1s3hDapmfpGuRJSERVUXkK8xESjFJR3TUS0DiDMhRkESEl3isJnKycCamsDpx cJii0agW/Ocu69T4/IZFQhzdyMHXoR8KpN7lfu5tMbp2x6r1eY1N4LsBYgPtGkvEIK yXgQ1/I5mHCgChWRAxrSEtBW5PzJsvOQZomEPATA= Received: from smtp.vodafone.de (unknown [10.0.0.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by mr6.vodafonemail.de (Postfix) with ESMTPS id 4RdhKF3LS1z1y3S for ; Sun, 3 Sep 2023 06:13:21 +0000 (UTC) Received: from Gerda (p57b9d560.dip0.t-ipconnect.de [87.185.213.96]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp.vodafone.de (Postfix) with ESMTPSA id 4RdhK91hxPzMkrv for ; Sun, 3 Sep 2023 06:13:14 +0000 (UTC) From: ASSI To: cygwin@cygwin.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@jeffunit.com> <2cfbcf8d-911f-a64b-8916-12b005c9f6f6@Shaw.ca> <07386659-68b3-a35d-1402-22684f8e5755@Shaw.ca> <076456ca-2c5d-4bb3-a64b-97ed4bdd26ce@jeffunit.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 Content-Type: text/plain 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 List-Id: 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