From owner-freebsd-hackers@freebsd.org Sun May 19 15:42:30 2019 Return-Path: Delivered-To: freebsd-hackers@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 0203015B0E0D for ; Sun, 19 May 2019 15:42:30 +0000 (UTC) (envelope-from cse.cem@gmail.com) Received: from mail-io1-f47.google.com (mail-io1-f47.google.com [209.85.166.47]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) server-signature RSA-PSS (4096 bits) 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 B07D369A30 for ; Sun, 19 May 2019 15:42:28 +0000 (UTC) (envelope-from cse.cem@gmail.com) Received: by mail-io1-f47.google.com with SMTP id g84so9156794ioa.1 for ; Sun, 19 May 2019 08:42:28 -0700 (PDT) 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:reply-to :from:date:message-id:subject:to:cc; bh=/Csyzs8xm+Zetz6QoMG7p71y2CSq9y7H3MO0mCjIk4c=; b=btcjJ5gqt5M7DJDpJrQ3CfMKxlFRiZ7p85ELeh2TkirqtW53BJtwuO8ii3Qw0Jo48W DUrfvtIDQA2Mof4TlLt6ClXN+PFjlYz2W2EWCTaBY7pCBbfzinqXSrgYpk+iWrXlyOmQ fVmktumz5rmw6AqYJl+UGPqEGtvr2rrLzYwvEnWEyThWHaLFZjL1W+S1Q3niePVqHVjd JOypOykBdUn5nbnouh3aH4hTqn0W/ipieqnerLC/VHDVwkFMhBbCZ3PVbZDAcMeuKOxZ /6bjLGGaI7d4vHnOSaBL8kayfVsYnRW0k7nDkQWlzJQ6Df/I0dxAQ0HM2RzA4ngUJ1CI usRA== X-Gm-Message-State: APjAAAX1Z+k7M9olmlZ1wTQK0N/7rfKqJNgpHJ+UDD4/G62CsI2QOaJ3 lrMi1+NDN4I+q3r/ooSL0WwZZpK+ X-Google-Smtp-Source: APXvYqzdhOGir09WcTkl389HWvDflbRfNySgGmko0ZkH+RdKHxjx5F4rT8jSTmFhBxEmaDqepQTBLQ== X-Received: by 2002:a5e:9505:: with SMTP id r5mr38217845ioj.285.1558280080967; Sun, 19 May 2019 08:34:40 -0700 (PDT) Received: from mail-it1-f177.google.com (mail-it1-f177.google.com. [209.85.166.177]) by smtp.gmail.com with ESMTPSA id r9sm4962239ioj.9.2019.05.19.08.34.40 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 19 May 2019 08:34:40 -0700 (PDT) Received: by mail-it1-f177.google.com with SMTP id m141so19122070ita.3 for ; Sun, 19 May 2019 08:34:40 -0700 (PDT) X-Received: by 2002:a24:e10c:: with SMTP id n12mr23626372ith.89.1558280080217; Sun, 19 May 2019 08:34:40 -0700 (PDT) MIME-Version: 1.0 References: <20190519125505.GB6971@rpi3.zyxst.net> In-Reply-To: <20190519125505.GB6971@rpi3.zyxst.net> Reply-To: cem@freebsd.org From: Conrad Meyer Date: Sun, 19 May 2019 08:34:28 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: total configured swap exceeds maximum To: tech-lists Cc: "freebsd-hackers@freebsd.org" Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: B07D369A30 X-Spamd-Bar: ----- Authentication-Results: mx1.freebsd.org; spf=pass (mx1.freebsd.org: domain of csecem@gmail.com designates 209.85.166.47 as permitted sender) smtp.mailfrom=csecem@gmail.com X-Spamd-Result: default: False [-5.67 / 15.00]; TO_DN_EQ_ADDR_SOME(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; HAS_REPLYTO(0.00)[cem@freebsd.org]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:209.85.128.0/17]; REPLYTO_ADDR_EQ_FROM(0.00)[]; RCVD_COUNT_THREE(0.00)[4]; MX_GOOD(-0.01)[cached: alt3.gmail-smtp-in.l.google.com]; RCPT_COUNT_TWO(0.00)[2]; NEURAL_HAM_SHORT(-0.90)[-0.904,0]; FORGED_SENDER(0.30)[cem@freebsd.org,csecem@gmail.com]; IP_SCORE(-2.76)[ip: (-7.97), ipnet: 209.85.128.0/17(-3.50), asn: 15169(-2.27), country: US(-0.06)]; R_DKIM_NA(0.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:209.85.128.0/17, country:US]; FROM_NEQ_ENVFROM(0.00)[cem@freebsd.org,csecem@gmail.com]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; TAGGED_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-hackers@freebsd.org]; DMARC_NA(0.00)[freebsd.org]; MIME_TRACE(0.00)[0:+]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCVD_IN_DNSWL_NONE(0.00)[47.166.85.209.list.dnswl.org : 127.0.5.0]; RCVD_TLS_LAST(0.00)[] X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 19 May 2019 15:42:30 -0000 Tangent to this thread, but: On Sun, May 19, 2019 at 5:56 AM tech-lists wrote: > Then there's the thing about dump/panic. IIRC doesn't total swap have to > be at least size_of_ram ? It can be smaller if occasional failure is acceptable. Minidumps are on by default and only dump active pages. Additionally, dumpon_flags can set "-Z" for zstd compression in 12.x+. The numeric speed/compression level is configured with sysctl kern.kerneldump_gzlevel (perhaps misnamed at this point, but originally only supported gzip). In practice, Zstd compression can often achieve good compression at level 1 or 3, reducing the size of swap needed to store a complete dump by a factor of maybe 3 without significant slowdown to the dump process. Cheers, Conrad