From owner-freebsd-questions@freebsd.org Sun Jul 26 13:55:18 2020 Return-Path: Delivered-To: freebsd-questions@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 329CB360D2A for ; Sun, 26 Jul 2020 13:55:18 +0000 (UTC) (envelope-from 4250.82.1d4c20005afa500.4c8e2893ba91b78f62396bdd5690dc27@email-od.com) Received: from s1-b0c6.socketlabs.email-od.com (s1-b0c6.socketlabs.email-od.com [142.0.176.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4BF4Fd58Ytz4bqm for ; Sun, 26 Jul 2020 13:55:17 +0000 (UTC) (envelope-from 4250.82.1d4c20005afa500.4c8e2893ba91b78f62396bdd5690dc27@email-od.com) DKIM-Signature: v=1; a=rsa-sha256; d=email-od.com;i=@email-od.com;s=dkim; c=relaxed/relaxed; q=dns/txt; t=1595771718; x=1598363718; h=content-transfer-encoding:content-type:mime-version:references:in-reply-to:message-id:subject:cc:to:from:date:x-thread-info; bh=9KYSQOC7L9hTy9d21toZPdUTP1caUCNNMdMcByzMq2k=; b=Qfz0zAl0YT435Kzb67z5yG7IGlk3RKdOWhuC/ZTmASuWfjg3bv5Off2CKFMrEnqYoug9Xl2wUpLmMp+XN5Vb4EYw6aGFGA7Y1qPh1BspK5zcGHAXM+7Gn8tCnSO6fLMcRBhGs4RWmT1Lp3it2f5lSSquBfC4zodcX+VBdY3A9m0= X-Thread-Info: NDI1MC45Mi4xZDRjMjAwMDVhZmE1MDAuZnJlZWJzZC1xdWVzdGlvbnM9ZnJlZWJzZC5vcmc= Received: from r2.us-east-1.aws.in.socketlabs.com (r2.us-east-1.aws.in.socketlabs.com [142.0.191.2]) by mxsg2.email-od.com with ESMTP(version=Tls12 cipher=Aes256 bits=256); Sun, 26 Jul 2020 09:55:14 -0400 Received: from smtp.lan.sohara.org (EMTPY [185.202.17.215]) by r2.us-east-1.aws.in.socketlabs.com with ESMTP(version=Tls12 cipher=Aes256 bits=256); Sun, 26 Jul 2020 09:55:13 -0400 Received: from [192.168.63.1] (helo=steve.lan.sohara.org) by smtp.lan.sohara.org with smtp (Exim 4.92.3 (FreeBSD)) (envelope-from ) id 1jzh7P-0007qb-Sx; Sun, 26 Jul 2020 14:55:12 +0100 Date: Sun, 26 Jul 2020 14:55:11 +0100 From: Steve O'Hara-Smith To: Aryeh Friedman Cc: FreeBSD Mailing List Subject: Re: Ask stupid questions and you'll get a stupid answers, was: Technological advantages over Linux Message-Id: <20200726145511.558d53ab7958c3c489b09a17@sohara.org> In-Reply-To: References: <20200214204838.360c8f624397c659946bd764@sohara.org> <6318251A-973A-4DEC-9271-12333EB11F7B@kicp.uchicago.edu> <20200725152412.GJ92589@admin.sibptus.ru> <20200725162403.GA4721@admin.sibptus.ru> <20200725182554.deffc63058a7c9f6d343ef06@sohara.org> <04df312d-9b2b-1873-2117-79a49e089bd9@kicp.uchicago.edu> <20200726074655.b0036a0f90508156205376f9@sohara.org> <20200726134331.5c960f7f93d76d2249bd769c@sohara.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; amd64-portbld-freebsd12.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4BF4Fd58Ytz4bqm X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=email-od.com header.s=dkim header.b=Qfz0zAl0; dmarc=none; spf=pass (mx1.freebsd.org: domain of 4250.82.1d4c20005afa500.4c8e2893ba91b78f62396bdd5690dc27@email-od.com designates 142.0.176.198 as permitted sender) smtp.mailfrom=4250.82.1d4c20005afa500.4c8e2893ba91b78f62396bdd5690dc27@email-od.com X-Spamd-Result: default: False [-2.98 / 15.00]; ARC_NA(0.00)[]; RWL_MAILSPIKE_VERYGOOD(0.00)[142.0.176.198:from]; R_DKIM_ALLOW(-0.20)[email-od.com:s=dkim]; NEURAL_HAM_MEDIUM(-1.00)[-0.995]; FROM_HAS_DN(0.00)[]; MV_CASE(0.50)[]; R_SPF_ALLOW(-0.20)[+ip4:142.0.176.0/20]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[sohara.org]; NEURAL_HAM_LONG(-0.99)[-0.989]; RCVD_COUNT_THREE(0.00)[4]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[email-od.com:+]; RCPT_COUNT_TWO(0.00)[2]; RCVD_IN_DNSWL_NONE(0.00)[142.0.176.198:from]; NEURAL_HAM_SHORT(-1.29)[-1.293]; FREEMAIL_TO(0.00)[gmail.com]; FORGED_SENDER(0.30)[steve@sohara.org,4250.82.1d4c20005afa500.4c8e2893ba91b78f62396bdd5690dc27@email-od.com]; MIME_TRACE(0.00)[0:+]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:7381, ipnet:142.0.176.0/22, country:US]; FROM_NEQ_ENVFROM(0.00)[steve@sohara.org,4250.82.1d4c20005afa500.4c8e2893ba91b78f62396bdd5690dc27@email-od.com]; MID_RHS_MATCH_FROM(0.00)[] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 26 Jul 2020 13:55:18 -0000 On Sun, 26 Jul 2020 09:04:02 -0400 Aryeh Friedman wrote: > On Sun, Jul 26, 2020 at 8:43 AM Steve O'Hara-Smith > wrote: > > > Here is a variant of your experiment that should demonstrate it. > > > > 1: Reboot machine, measure performance > > 2: Memory stress machine to until swapping reduces performance > > 3: Kill memory stressing process > > 4: Disable swap - which forces all pages back into RAM > > 5: Enable swap > > 6: Loop to 2 > > > > Since stealing memory from a running process that counts on it to be > functional will crash the process and odds are that process is something > low level and critical to keeping X running the above variant is not > practical to do and thus my current solution has the same effect -- > reboot. It is very practical and it is the way I normally recover a system from a memory usage spike, it works far better than just leaving it alone. Nothing in that steals memory from running processes. -- Steve O'Hara-Smith | Directable Mirror Arrays C:\>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | http://www.sohara.org/