From owner-freebsd-stable@freebsd.org Tue Apr 17 16:05:53 2018 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 2F6A3F869A2 for ; Tue, 17 Apr 2018 16:05:53 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-lf0-x235.google.com (mail-lf0-x235.google.com [IPv6:2a00:1450:4010:c07::235]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 7963371C49 for ; Tue, 17 Apr 2018 16:05:52 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: by mail-lf0-x235.google.com with SMTP id z130-v6so2600558lff.5 for ; Tue, 17 Apr 2018 09:05:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=Ux0PtBKQ0+LXDSMwx62JJJVU6gCHUlGWESXhN/VSlBA=; b=gJx8NTy64FvajLYx0Cm8t3KaPmKew03qq2cOjXt8heLy4d0qRr4f2l8BVm0+635E25 nJfu9F6/DStH39pqcB3Wi6lF2khDdky/NbybJTKRsZGENlDOCNUWXLYnJf7DjvvM+VM2 23x9M7T4mqL6zFLMKJu2PGJc+r2Ykvjb38y3X9NxoyM9kXKkT06WOrpqNz4oygNsyZ2a KELQrOc1/QU6lpjnZfZGA8nxiRu3Nc2e4z1jIahwqDaVUkpfEoxya9/YI0sE1UixIgFW UbhgczZiweYYnfOwW0rBPputCnnMfY/twQYxkGcCwnPeUErnKZAX9i0kowSNkVLUgiSD Nl3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=Ux0PtBKQ0+LXDSMwx62JJJVU6gCHUlGWESXhN/VSlBA=; b=jmi5BNOuo8YtyuokVsuK8lYtJRsHCNvde30+iNqVK1oe7X8O1m8NQKIYvlNQu+jmqE bm47yl6+euTJzcKINr4TResN+O+bd4JXXOj+bAEUxLk3ecTBl7bDXSv9ZOUJFYFQZWJ7 Ye6XApShFkCifSh1AKunQ4Dr7V6W1bOaZgvXuaGiopH85xW5M3Pf93U4q6yM7t2lx4eX j0E38M6HnFBPwwaiOTC360mKYodys2vNLZsbIMEFuKCkMkil1/bZFQraHe0lKme0FUp1 kAMhv+efq0lcZRcLue3bsjW/KEa4puP0hfTCqnJYVgBHsq8u53vhTs6tPHfahQgakN/a 0JVw== X-Gm-Message-State: ALQs6tAhJZXhwKOWVHv2f+79wYroJVQjobS09AeBsv1mx+fkFdzG5rIo pn4Xh/VJ6nJH110/hGoYrcp4xqJuA3ir6ZVcmVs= X-Google-Smtp-Source: AIpwx48+MgF0H+3RCniM4jRwRMoCgpG0lcDk5B3yNAdtZsQXAMy+ltCqT3e2XFAPJ5wk4sqXqo6iCIODp8fIck7LIbw= X-Received: by 2002:a19:974e:: with SMTP id z75-v6mr2097416lfd.41.1523981149383; Tue, 17 Apr 2018 09:05:49 -0700 (PDT) MIME-Version: 1.0 Received: by 10.46.2.25 with HTTP; Tue, 17 Apr 2018 09:05:48 -0700 (PDT) In-Reply-To: References: <9FDC510B-49D0-4722-B695-6CD38CA20D4A@gmail.com> <8cfdb8a3-86a0-17ba-1e41-ff1912a30ee9@m5p.com> <20180417065617.GA95646@klump.hjerdalen.lokalnett> From: Freddie Cash Date: Tue, 17 Apr 2018 09:05:48 -0700 Message-ID: Subject: Re: kern.sched.quantum: Creepy, sadistic scheduler To: Kevin Oberman Cc: Eivind Nicolay Evensen , George Mitchell , FreeBSD-STABLE Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Apr 2018 16:05:53 -0000 On Tue, Apr 17, 2018 at 8:49 AM, Kevin Oberman wrote: > On Mon, Apr 16, 2018 at 11:56 PM, Eivind Nicolay Evensen < > eivinde@terraplane.org> wrote: > > > On Wed, Apr 04, 2018 at 09:32:58AM -0400, George Mitchell wrote: > > > On 04/04/18 06:39, Alban Hertroys wrote: > > > > [...] > > > > That said, SCHED_ULE (the default scheduler for quite a while now) > was > > designed with multi-CPU configurations in mind and there are claims tha= t > > SCHED_4BSD works better for single-CPU configurations. You may give tha= t > a > > try, if you're not already on SCHED_4BSD. > > > > [...] > > > > > > A small, disgruntled community of FreeBSD users who have never seen > > > proof that SCHED_ULE is better than SCHED_4BSD in any environment > > > continue to regularly recompile with SCHED_4BSD. I dread the day whe= n > > > that becomes impossible, but at least it isn't here yet. -- Geor= ge > > > > Indeed 4bsd is better in my case aswell. While for some unknown to me > > reason ule performed a bit better in the 10.x series than before, in 11= .x > > it again is in my case not usable. > > > > Mouse freezes for around half a second with even frequency by just movi= ng > > it around in x11. Using 4bsd instead makes the problem go away. > > I'm actually very happy that ule became worse again because going > > back to 4bsd yet again also gave improved performance from other > > dreadfully slow but (to me) still useful programs, like darktable. > > > > With 4bsd, when adjusting shadows and highlights it is possible to see > > what I do when moving sliders. With ule it has never been better than > waiting > > 10-20-30 seconds to see where it was able to read a slider position > > and update display, when working on images around 10500x10500 greyscale= . > > > > It's not single cpu/single core either: > > CPU: AMD FX(tm)-6300 Six-Core Processor (3817.45-MHz > K8-class > > CPU) > > My experience has long been that 4BSD works far better for interactive, X > based systems than ULE. Even on 10 I saw long, annoying pauses with ULE a= nd > I don't se those with 4BSD. I'd really like to see it better known that > this is often the case. BTW, my system is 2 core/4 thread Sandybridge. > =E2=80=8B > =E2=80=8BThe following has been suggested multiple times over the years on = various mailing lists as the "solution" to making ULE work well for interactive tasks like running X-based desktops (in /etc/sysctl.conf):=E2=80=8B # Tune for desktop usage kern.sched.preempt_thresh=3D224 =E2=80=8BWorks quite nicely on a 4-core AMD Phenom-II X4 960T Processor (3010.09-MHz K8-class CPU) running KDE4 using an Nvidia 210 GPU. --=20 Freddie Cash fjwcash@gmail.com