From owner-freebsd-questions@freebsd.org Tue Jun 19 08:09:25 2018 Return-Path: Delivered-To: freebsd-questions@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 CEE741005360; Tue, 19 Jun 2018 08:09:24 +0000 (UTC) (envelope-from freebsd.ed.lists@sumeritec.com) Received: from mx18-out13.antispamcloud.com (mx18-out13.antispamcloud.com [207.244.64.182]) (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 B6F1D7216B; Tue, 19 Jun 2018 08:09:23 +0000 (UTC) (envelope-from freebsd.ed.lists@sumeritec.com) Received: from [153.92.8.106] (helo=srv31.niagahoster.com) by mx18.antispamcloud.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1fVBhU-0000ZD-Q8; Tue, 19 Jun 2018 10:09:22 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sumeritec.com; s=default; h=Content-Transfer-Encoding:Content-Type: MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=2B1+zNULM2tQykPwu1VeBunT1oW50i8mGz9y1LVHPbA=; b=WIM4iBnzc1Hp38OUAEYCAGVjgi W+uzuQtexV9H/yW42gaa/jm4OXv6g8tq1rPzdpMjw0Sxv3jV22FTz8NnMrOgSZ74PHMXVatpAsw1o A2nsRV0MsI/r7Eia2Tl2R0uFDMb7P5JSXuW8n6WbNFOuzpr1n+QkbsgWG3+xgF7DvKoCjoyUBiDlr ixGTHDPXk0Rqj8kXwqv761ih2w2Q38+2IDTMqUcGw4iHnPKkGS+h2CVhZc/MM8GA4q2OJvgUX8krP 3YKz1004qv8OsOWTfOjxbeBcH/AaDgYptfW+fNpNqzYnJWYkwyF7UEHUuMApu93/EwBrwOf5xkj1B kO3kreHA==; Received: from [114.125.71.15] (port=62491 helo=X220.sumeritec.com) by srv31.niagahoster.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1fVBge-0009WC-Qf; Tue, 19 Jun 2018 15:08:27 +0700 Date: Tue, 19 Jun 2018 16:08:22 +0800 From: Erich Dollansky To: Stefan Esser Cc: tech-lists , freebsd-stable@freebsd.org, freebsd-questions@freebsd.org Subject: Re: lightly loaded system eats swap space Message-ID: <20180619160822.028aedd5.freebsd.ed.lists@sumeritec.com> In-Reply-To: <7fdc922c-ba19-c822-6f6e-d768533a2876@freebsd.org> References: <20180618160855.44d9a0c2.freebsd.ed.lists@sumeritec.com> <20180619094826.75c0c735.freebsd.ed.lists@sumeritec.com> <7fdc922c-ba19-c822-6f6e-d768533a2876@freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-OutGoing-Spam-Status: No, score=-1.0 X-AuthUser: freebsd.ed.lists@sumeritec.com X-Originating-IP: 153.92.8.106 X-AntiSpamCloud-Domain: out.niagahoster.com X-AntiSpamCloud-Username: niaga Authentication-Results: antispamcloud.com; auth=pass (login) smtp.auth=niaga@out.niagahoster.com X-AntiSpamCloud-Outgoing-Class: unsure X-AntiSpamCloud-Outgoing-Evidence: Combined (0.16) X-Recommended-Action: accept X-Filter-ID: EX5BVjFpneJeBchSMxfU5usdY7E8KpTqno+Z301XEgF602E9L7XzfQH6nu9C/Fh9KJzpNe6xgvOx q3u0UDjvO4N5oQrZbCLfV7hJyljfOmfn6HaatznLU8a/oEUKfeIg/I6Frex1icm8Z5xovxYmeLlr qv8bccGjjcGuRJYc3CsRb3caiKydq8Z8Xbc5Vf6x2koUe6H4EgsR4KI2aZpsc6BPex1XXjYLerSq l+GM0oyqNgIHQ5dF9dtv8nnICvNYsOZUZ3LpX5sVKofsd4Ljn0SITl3F8isfnMI2tq4ALYmhFfT8 SX4c9CyvMRbQCZoBVgW9/bktU41htiJ8fk7NkEYjFo+uebo6mh5wy9P2cSKVjS1iAWRHBDDqjVRq rxKNcbyOkcjQN+Nad0B5PTkOY6yMT6yKWg7axbe8p2uiBYKlk6iLOvzJGCYfseu8gWUSAhrohMZt WSIoElgwDHfdIIkB1/R4ar1CYVgFKOoJD16tNj2rE+TJPq42zd+nDKsqKvWTUIuwAP+Be6QqMx/O K6S8tu2KVBI79Uufvsp4JVu/xPrargplL/tPsMC2s+w8vKhXliG78w9pKdlOmjaruM9jtS6Zuw56 NzJ4HoAbKeEtjEbRrFHvESnMqzLGulVo1Bnfpi+LPGsUlkOs7d49CmiH1Wgh6RAenBR+licROGZz MdrUQXpciqnq9qOjh4etVCt6wkGNBO7fECYEaHetw/Vz0MrRTeKdVDNlYSch1/L5XH68VhUGuWyN oOWkK0Uio9orsOc0u3VU19a+ctSrw6ntKr6+crm+rffkaQ6ZgOiaWu8ipdKNsU8IFBbqK4pIIhsw sD/LeXoEtIo9KOeLwYoK0XEeLExv6RoSf29nwNyXAHQFv25JRzDZU4hg3424zkzvfc03RW0sZulU a+392X6m+UeFXprlCOm3BAEbJtDc4+l+WWuYiTAZMJQK5ses+d5GWWc/u6JOjtOJBa9uhxminqBI 3nGd34AYLmTpVeFbLPp9n350Mbemie5JWWm/Mwqvvyz63pRF7yCn+1yLJJE4hKzEl0g6eZTimdco TomlgJLhZDkE6UMGbRwzU4S8 X-Report-Abuse-To: spam@quarantine1.antispamcloud.com X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 19 Jun 2018 08:09:25 -0000 Hi, On Tue, 19 Jun 2018 09:06:42 +0200 Stefan Esser wrote: > Am 19.06.18 um 03:48 schrieb Erich Dollansky: > > A very long time ago - and not on FreeBSD but maybe on a real BSD - > > I worked with a system that swapped pages out just to bring it back > > as one contiguous block. This made a difference those days. I do > > not know if the code made it out of the university I was working > > at. I just imagine now that the code made it out and is still in > > use with the opposite effect. > > If this was on a VAX, then it was due to a short-coming of the > MMU of the VAX, which used one linear array (in system virtual this could have been the case as they have had many DEC systems. > Nothing of the above applies to any other architecture than the > VAX and thus the swap-out of all user processes serves no purpose > on any other system. It was an implementation detail of the VAX > VM code, not a BSD Unix feature. I know how an MMU works, but I also know how caches work. It still could give a tiny advantage if it is in one piece, even if it is not a requirement to function. Any way, I do not work in this area anymore. Erich