From owner-freebsd-stable@freebsd.org Fri Jun 26 11:57:12 2020 Return-Path: Delivered-To: freebsd-stable@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 3A1DB356086 for ; Fri, 26 Jun 2020 11:57:12 +0000 (UTC) (envelope-from dwilde1@gmail.com) Received: from mail-lj1-x22e.google.com (mail-lj1-x22e.google.com [IPv6:2a00:1450:4864:20::22e]) (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 49tb3C2Tydz4X2Z; Fri, 26 Jun 2020 11:57:09 +0000 (UTC) (envelope-from dwilde1@gmail.com) Received: by mail-lj1-x22e.google.com with SMTP id s9so9992544ljm.11; Fri, 26 Jun 2020 04:57:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:reply-to:in-reply-to:references:from:date:message-id :subject:to:cc:content-transfer-encoding; bh=s8oHqTzXR6Rr/FQ6aR0oUrIYTFxBV9bdkA2JB/HnkIg=; b=JbhOJOIowP6+HToyv//RZ1fgO0RstDdXXXt6XcaQoRoo0fKXk04Rb77LUS0CsweE30 cJaVjFCeRJQ4njCWN/HPPxeEiDcnEECncDETlVTKzNlMr5OFAvkJyrgy4I4WAoT90iW9 cgKhlLLVOWSy4ox1yYjZDco4+BgycCpuYxIDKgOwCsrb4E5DZSnvDYcTgld7/oHSgK8l OA6bJdxVaoDigCvk0ulTssS0wiW1MVNEkIoacPXBmK7J+3cVzucl8Inwh7Lzuyloi3E4 8+io67Lj2dcXpFEB3Ug8CyArT8zXon0dmcSgt0MkB53FVsBeaYjvfbGQR6boEveBMLf9 6I+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:reply-to:in-reply-to:references :from:date:message-id:subject:to:cc:content-transfer-encoding; bh=s8oHqTzXR6Rr/FQ6aR0oUrIYTFxBV9bdkA2JB/HnkIg=; b=ThPjt1Vulh1B++WB0/FJHQTGxM3n66Km19V5XVSKPjHsdhuRtPGYj1oFIdyvP2Taex yLIxP3t4vKmfmx8fgEPKCpIQCoqr8sGJZ5VLFe3VQ1Qt0FCiHXCpQ/rtRG1Yjqx4NjwD nicSTH+jBqBydKL7snR4FfEM7zdRFyG+VsNwTz3DHhhjITJ4fSWo//Nt32CVY1cCmaKE nr4adzR80L0I+NAzeZWMUhz9F6dFRw2XBQoWPbYA+qFQhE8dtTD60FEVtoYyfEY+2zYK cVHxBnBDHSoo9fkWxn52WgmD5AETe1ZldnlW3PXcRZN4JZa5ug+Cz+7qfncVhL4qfx7c g9+Q== X-Gm-Message-State: AOAM533WCvFphFJzbLE8Qw+bMm5eSSKC3quBORWdDQoBthy/wBgObBH7 ZinFpCCkARE+JbNSZadwRAiwJPlytEaYGHmoDxo0FUZA X-Google-Smtp-Source: ABdhPJwB88QhfIHw+MZWvJmv8of83YTvwdFBNPYa0q0hhwHzfQ8fQSwemzRFOSbhFekOpUKpBZioSOGIpmkmyAp0xZI= X-Received: by 2002:a2e:580f:: with SMTP id m15mr546638ljb.357.1593172626640; Fri, 26 Jun 2020 04:57:06 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:ab3:4703:0:0:0:0:0 with HTTP; Fri, 26 Jun 2020 04:57:05 -0700 (PDT) Reply-To: dwilde1@gmail.com In-Reply-To: <52753cf4-57db-93d9-d217-c8f812d6bc7c@freebsd.org> References: <20200625000410.GA10210@eureka.lemis.com> <20200625025248.GB10210@eureka.lemis.com> <20200626102331.GA6406@server.rulingia.com> <52753cf4-57db-93d9-d217-c8f812d6bc7c@freebsd.org> From: Donald Wilde Date: Fri, 26 Jun 2020 04:57:05 -0700 Message-ID: Subject: Re: swap space issues To: =?UTF-8?B?U3RlZmFuIEXDn2Vy?= Cc: freebsd-stable@freebsd.org, Peter Jeremy Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 49tb3C2Tydz4X2Z X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; REPLY(-4.00)[] X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Jun 2020 11:57:12 -0000 On 6/26/20, Stefan E=C3=9Fer wrote: > Am 26.06.20 um 12:23 schrieb Peter Jeremy: >> On 2020-Jun-25 11:30:31 -0700, Donald Wilde wrote: >>> Here's 'pstat -s' on the i3 (which registers as cpu HAMMER): [snip] > An idea for a better strategy: > > It might be better to use an allocation algorithm that assigns a > swap device to each running process that needs pages written to the > swap device and only assign another swap device (and use if from > then on for that process) if there is no free space left on the one > used until then. > > Such a strategy would at least reduce the number of processes that > need all configured swap devices at the same time in a striped > configuration. > > If all processes start with the first configured swap device assigned > to them, this will lead to only one of them being used until it fills > up, then progressing to the next one. > > The strategy of whether the initial swap device assigned to a process > is always the first one configured in the system, or whether after > that could not be used by some process is moved on to the next one > (typically the one assigned to that process for further page-outs) is > not obvious to me. You're getting over my head, STefan, but that's okay. I suspect that having somebody be loony -- and desperate enough -- to configure two swap partitions is a rare occurance. > > The behavior could be controlled by a sysctl to allow to adapt the > strategy to the hardware (e.g. rotating vs. flash disks for swap). Not to mention Intel and Micron and their fancy fast non-volatile chips ('Optane'). I do agree that SOMEBODY is going to need this kind of sysctl guidance for the kernel. > [snip] > And while it does not come up that often in the mail list, it might > be better for many kinds of application if the default was increased > (a longer wait for resources might be more acceptable than the loss > of all results of a long running computation). Yes. Synth seems to be able to keep going / recover from last-known success points, but your point is very valid. As we go further into OOP, the _controllable_ use of heap space, stack space, and recursion is going to become more crucial. We humans are used to operating without a "full stack," (sleep DOES help :) ) but I think the whole point of modern AI is to create systems that actually can master the logical inference chains proposed by the early LISP guys at MIT, C-M, and Stanford. The gains from ML have been enough to keep 'the Street' happy for now but they'll want more soon enough. > Regards, STefan Thought-provoking indeed. :D --=20 Don Wilde **************************************************** * What is the Internet of Things but a system * * of systems including humans? * ****************************************************