From nobody Tue Jul 13 22:24:15 2021 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 98D49124197B for ; Tue, 13 Jul 2021 22:24:29 +0000 (UTC) (envelope-from zbeeble@gmail.com) Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GPZtj3YT0z3w0v for ; Tue, 13 Jul 2021 22:24:29 +0000 (UTC) (envelope-from zbeeble@gmail.com) Received: by mail-ej1-x629.google.com with SMTP id go30so17226107ejc.8 for ; Tue, 13 Jul 2021 15:24:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=eXRBmsa0r/Foc2h6aA/7bqPIn1SgDu1L4SMWWHHLN24=; b=I2T+IX5AInmAkULykVJSbZUiAvubrQJOe/vp2PDas0LzZafz6UczLho4GGOlDoAjIh WHg1PD60ea5u/GExqLtul3x95NdsHkqvBW3IuXLYx3MgBOaNhHcfDS0jtsYh6oEJFVVk 6hSU3se476rhwj2TtosFKviX/8/2IXL+Unbn4ymqQ2T76mBs2y/1THOtXT61ZhxdUe+1 jXol/3cFx26QxaMJiQXyAEZVgiHLIvKXOH8P74xfyYEkOxnyPX6SQ6u6xCsmyzcX699/ WOHAzryq2CHFanpKXtA9+OkEKWsIWhxsm6rSYVoLdIipeMrxGLK/DK9jJjZaZkcxiCOu NO9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=eXRBmsa0r/Foc2h6aA/7bqPIn1SgDu1L4SMWWHHLN24=; b=l4p5DX3PtL+zl8mGNeENk5G2wroOocDzTXtgRnTyD/i2ahIV4BZRgV/to9LCigVXYw RbBFPO/1vebZp3dcF1xY+k33hjeNb0GLPBwD2b2vu2Jgvqj4mRZ4vqM9yAIr2RP3qHxB a2HiWMIYzAjYWVao0YKPhdV61XVbUcufWft5ICbR++pHILLRfwn/nvTOaEwQOfuRzAce Re7bBonfORWLOThXKOdwSLrk58i8Skz7n0DnpwWdTIkV/YDtOPzH2hyVVwhLRs95ceQf bkMBm6hY8dkdK7XgxpzJfMfFa9fwwDXSKXzClnqj8Ix1NpkOJmtQAzSYgE5CUr82kNlS h1IA== X-Gm-Message-State: AOAM533prnn8dV9CQ9hmE654DExwSrZVo6aXwUcGPxWyA1eFWaDQNYeB HDkN8WNJwv4/NfmZQSQKT6VIyeLYSm1qJqIlvuQi6vIALA== X-Google-Smtp-Source: ABdhPJyAGgk+9czuinyiu8P9sqSQ2EpABJHyzTErXOX46EelRmMBfVlHs3Iu7DsFEA/TOH1keQ9BzKW6hkjwVGGp7Dc= X-Received: by 2002:a17:907:62a5:: with SMTP id nd37mr8243503ejc.148.1626215067072; Tue, 13 Jul 2021 15:24:27 -0700 (PDT) List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 References: <13445948-7804-20b4-4ae6-aaac14d11e87@m5p.com> <20210708101907.0be3a3c2@rimwks.local> In-Reply-To: From: Zaphod Beeblebrox Date: Tue, 13 Jul 2021 18:24:15 -0400 Message-ID: Subject: Re: Periodic rant about SCHED_ULE To: George Mitchell Cc: Rozhuk Ivan , FreeBSD Hackers Content-Type: multipart/alternative; boundary="00000000000066bbae05c708b33a" X-Rspamd-Queue-Id: 4GPZtj3YT0z3w0v X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; TAGGED_RCPT(0.00)[freebsd]; REPLY(-4.00)[] X-ThisMailContainsUnwantedMimeParts: Y --00000000000066bbae05c708b33a Content-Type: text/plain; charset="UTF-8" Also, TBH, I think the goals, proof that algorithm meets the goals and then code is one of the shining examples of FreeBSD engineering. It's one of the things I point to when people ask why I like FreeBSD (after the licence and the governance)... and thats in sched_4bsd.c. On Tue, Jul 13, 2021 at 6:21 PM George Mitchell wrote: > On 7/13/21 6:09 PM, Zaphod Beeblebrox wrote: > > [...] > > TBH, I think SCHED_ULE is a failure and the only reason more people don't > > think so is that processors are now largely too fast for people to care. > > [...] > I won't call it a failure, but I will call it the wrong default for the > GENERIC build. And you're certainly right about why people don't care. > -- George > > > > I know we don't have guiding principles for nice, but I would toss out > the > > +/- five rule for it --- that any process more than 5 nice levels lower > > from a cpu-busy process shouldn't preempt the higher process. I realize > we > > have rtprio, but it's a pain to use. Anyways, don't let this last > comment > > distract. > > [...] > > --00000000000066bbae05c708b33a--