From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98092EB64DD for ; Fri, 21 Jul 2023 18:37:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230107AbjGUShr (ORCPT ); Fri, 21 Jul 2023 14:37:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229451AbjGUShp (ORCPT ); Fri, 21 Jul 2023 14:37:45 -0400 Received: from mail-pl1-x630.google.com (mail-pl1-x630.google.com [IPv6:2607:f8b0:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 559EA30C8; Fri, 21 Jul 2023 11:37:44 -0700 (PDT) Received: by mail-pl1-x630.google.com with SMTP id d9443c01a7336-1b8bd586086so16844175ad.2; Fri, 21 Jul 2023 11:37:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1689964664; x=1690569464; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=N41yylWGWk71mjRvficRYzreADvXSZZyopesyI5c/L0=; b=ItOwTjjykBhLM1ay/9YyR+ZsbNhldD2jAOoNzfbst+7UcSlEKQCo6wgI31GHcZeW5R 3u0X0YBFTisbwOojTVKXdzM7F+Rx1Y9364uz8fMYZNm87AKf3UYKBpIsvOiCE4OWkK6A 1oisXWXlNX5C/J1KbqxucVShx30LOG6J8VI+Ew8aK112TPju3avalwMqCkGvLiFRDdiW CHL/JxOmQjrzXyilHzB8i95MrJ+vr02J8B7ht9/pjcvP7VzcDiApl6uDuhK/edX+TNRv PKt2iZeYacNw6dPGnXG7rtYR9NbLC/t2sk/pa6s9Kt19umFNLhu15dbB5ziqjivdTEqF +QnQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689964664; x=1690569464; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=N41yylWGWk71mjRvficRYzreADvXSZZyopesyI5c/L0=; b=jQyw9eOc9IxfE5bJrHWmjclA+qydVOH8UYHFujJyxyiJtf29HU+dxWLjXFcwCN7cER aLYObzdsolhxO+HyY3Z4mTBYQgit5VeX90Q56vbVTqDU5Qgdf5lnksh+aRckEC3qJ82S yLu2n7978g3yt+yf1IbU3Wd+P+RrUa12wXnS3j/rQQzJnT/qulzyLaxpc6NVgZ2q/l45 3JuU02ZrANyUJhW5WM/iTGFy5OlsBjsiqBEvY5JAKsA64sC5m6/9+wyyiPiI9qLSAGlG Vd6B0B9amUdNlH0WYYdpRTlbKyKwWr9ofMYIOdBXBnJHOMNzgJhvjm/YtJ98YQO1a6dI OSlQ== X-Gm-Message-State: ABy/qLagP20upHv9BdmAJfYO2jgU/cvNtgM84zIwSoT9ESLyTbRbLGk5 ncFJ7NeMHyJDS8j0bI+1fqo= X-Google-Smtp-Source: APBJJlFK6CZrZMkCL+nsu5Sg8SMHY9EMPqQvH9QY2wSeL9Dj4fDuQCzK/6dXQPmDjxKEXsIxINu5mA== X-Received: by 2002:a17:902:e74a:b0:1b8:9b1d:9e24 with SMTP id p10-20020a170902e74a00b001b89b1d9e24mr3276832plf.22.1689964663568; Fri, 21 Jul 2023 11:37:43 -0700 (PDT) Received: from localhost ([2620:10d:c090:400::5:fbd8]) by smtp.gmail.com with ESMTPSA id h7-20020a170902f7c700b001b8528da516sm3842958plw.116.2023.07.21.11.37.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Jul 2023 11:37:43 -0700 (PDT) Sender: Tejun Heo Date: Fri, 21 Jul 2023 08:37:41 -1000 From: Tejun Heo To: torvalds@linux-foundation.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, joshdon@google.com, brho@google.com, pjt@google.com, derkling@google.com, haoluo@google.com, dvernet@meta.com, dschatzberg@meta.com, dskarlat@cs.cmu.edu, riel@surriel.com Cc: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCHSET v4] sched: Implement BPF extensible scheduler class Message-ID: References: <20230711011412.100319-1-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230711011412.100319-1-tj@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, It's been more than half a year since the initial posting of the patchset and we are now at the fourth iteration. There have been some reviews around specifics (should be all addressed now except for the ones Andrea raised on this iteration) but none at high level. There also were some in-person and off-list discussions. Some, I believe, are addressed by the cover letter but it'd be nonetheless useful to delve into them on-list. On our side, we've been diligently experimenting. A lot of our earlier experiments were focused on improving work conservation which led to the CFS shared runqueue patchset that David Vernet is currently working on. The workqueue experiments which led to PeterZ's SIS_NODE patch was also informed by the same work conservation experiments. We also played with soft affinity which is inspired by Julia's nest scheduler. Another thing we recently learned was that at least for our web workload, L1/2 locality doesn't matter much. This is an area of on-going experiments. We are comfortable with the current API. Everything we tried fit pretty well. It will continue to evolve but sched_ext now seems mature enough for initial inclusion. I suppose lack of response doesn't indicate tacit agreement from everyone, so what are you guys all thinking? Thanks. -- tejun