From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6703C43603 for ; Tue, 17 Dec 2019 06:30:10 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8081C21739 for ; Tue, 17 Dec 2019 06:30:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8081C21739 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vt.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.92.3) (envelope-from ) id 1ih6Mb-0001W8-L4; Tue, 17 Dec 2019 01:29:45 -0500 Received: from omr1.cc.ipv6.vt.edu ([2607:b400:92:8300:0:c6:2117:b0e] helo=omr1.cc.vt.edu) by shelob.surriel.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.3) (envelope-from ) id 1ih6MZ-0001W0-9O for kernelnewbies@kernelnewbies.org; Tue, 17 Dec 2019 01:29:43 -0500 Received: from mr4.cc.vt.edu (mail.ipv6.vt.edu [IPv6:2607:b400:92:9:0:9d:8fcb:4116]) by omr1.cc.vt.edu (8.14.4/8.14.4) with ESMTP id xBH6Te5C017761 for ; Tue, 17 Dec 2019 01:29:41 -0500 Received: from mail-qv1-f71.google.com (mail-qv1-f71.google.com [209.85.219.71]) by mr4.cc.vt.edu (8.14.7/8.14.7) with ESMTP id xBH6TZct020679 for ; Tue, 17 Dec 2019 01:29:40 -0500 Received: by mail-qv1-f71.google.com with SMTP id 75so6937977qva.8 for ; Mon, 16 Dec 2019 22:29:40 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=8Kp7l/hcGpgjChMif/evkt/Mg8dHbpZzFjYRt/FYfJk=; b=bpeQfR+QzGbhtsLztcob6ulke1QRcqfass4AuOPTPaWGSa+Lnz7KmQEEl080Qp/obL KvQ1NTo/JKLfkN1zcsE7c+olTRxUi/q9WPZPHuyuXCrHKV9DVgjUBvofCrJvdNFGoJ3m BgHsy2n2LDQyLfmBHv2tvF14hCeKYhVCfSd12eyq1L5YhmaEJcBInklw28zUKNT1U5Od FSEp7HZEqYxKngxpaC+b2J2TgQAEyrkL7sCyQElBx6kU64D6E/ZQuwOwzb0peLyur91Z WnigSyubHBd3VzK1If1J62IteTRT4HADDs3YpGzYePzsPFk8zlrM6bOsYfoLxfiwNcZA fb2w== X-Gm-Message-State: APjAAAVR18nsREed/yUHeK6E5Qpj476TA2wZS/P2YdJBBqf9Kj83cS3Q DU/HVDzt52bjLNuf3G99ZHsZctfg2JhWLmKc67oMwkGqQ8ezGHbgqCVoymfo12V4r4qqiMOV3PQ osbFbf4LRq/ZpLND/a/8dZH+AiLfcp7vKKItyaqI= X-Received: by 2002:a05:620a:1114:: with SMTP id o20mr3435311qkk.128.1576564175670; Mon, 16 Dec 2019 22:29:35 -0800 (PST) X-Google-Smtp-Source: APXvYqwsVoY3kuWUTH6pUQlUQEnfJe0Zi0WFx6VhDyajeMRSJSsQ26EgPBcBtSlZix3tkNTp5xe4Eg== X-Received: by 2002:a05:620a:1114:: with SMTP id o20mr3435294qkk.128.1576564175303; Mon, 16 Dec 2019 22:29:35 -0800 (PST) Received: from turing-police ([2601:5c0:c001:c9e1::359]) by smtp.gmail.com with ESMTPSA id q73sm6778249qka.56.2019.12.16.22.29.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Dec 2019 22:29:33 -0800 (PST) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: Neel chakraborty Subject: Re: Free RAM in Linux . In-Reply-To: References: Mime-Version: 1.0 Date: Tue, 17 Dec 2019 01:29:33 -0500 Message-ID: <183371.1576564173@turing-police> Cc: kernelnewbies@kernelnewbies.org X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============9018842972625439808==" Errors-To: kernelnewbies-bounces@kernelnewbies.org --===============9018842972625439808== Content-Type: multipart/signed; boundary="==_Exmh_1576564172_34200P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit --==_Exmh_1576564172_34200P Content-Type: text/plain; charset=us-ascii On Tue, 17 Dec 2019 10:39:08 +0530, Neel chakraborty said: > Does Linux use all of the physical memory (RAM) I have ? In both the > outputs of /proc/meminfo and free -h , shows that 1.4 gigs is used and 1.6 > gigs is cached , and the rest is "free" out of 32 Gigs . The available ram > is the cached ram + reclaimable ram + free ram , right ? That probably means that the processes you have running use a total of 1.4G of ram, and you've referenced 1.6G of files on disk. The rest is free because you've not done anything to give the system even a hint of what to do with the other 27G of RAM. If you reference a whole bunch of files (find /usr -type f | xargs cat) > /dev/null or other similar), you'll see more gigs used for cache. If you run a few large processes, like a Chrome with 90 tabs open, you'll see the other number go up. > And also , does the linux kernel use the amount of ram which is not used by > applications as paging cache ? Say I have 4 gigs of ram , and Firefox is > using 1 gig of it , the rest of RAM is used for disk/page caching or is it > just unused and left there ? The kernel itself will use some of it, other processes will use some of it, and if there's any left, it will be used for disk caching - but not until a process has actually referenced data off the disk. --==_Exmh_1576564172_34200P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.9.0 11/07/2018 iQIVAwUBXfh1zAdmEQWDXROgAQIyBBAAmSLo+w6JMVAw1GOlfnuYGgJZVbEpFzyi LTBM3nPQAVeFZfb1xMnqQX5eAgZG9T8sDNxYZDRtDeqTKcH9yA34OJ/UTc96IO0c kLTzdjXHONyzdZCgzXloU6UGEynkKHNK8OqTXQlbLk+2LLH6Ukt5sfWkJu8zdYcH lwYsIcF2ZthBexWizy/DBog84OorUk61bXbBHRlF1vqKxiefLW+iGZjlOoHtP2sM gHIVK/4Fy8fK32TWvUWSF4lIDEQqxlcA4Djp3UzLUiv9lPykGFTGx8kh0SNmiWHm p9T5GQS77cA9xe8RBO6c/uufYyxosIiCh3t19Sq4xApPX0S9pHQgonvybk6ji4S1 9ve9ggsLACaUTMnWStlZ1iURfUK6DXjOpMaER7btzADBxJsN1/VPwUFO1i8OGFfT c7djFs4z4B2UDKzR0EAJLKbrt88NqneqI3JV4q/un996tfLNTaQgvhhR+i6rpha8 jCB9LTJAcBYWKOB9ULHdYKfLeArHeNPSzi0/H6kcwXsbeJhBXCclwkLX1LXQdmKF 8jaU7aESGGrIiiqiqAucFRiTxiCPAwAwkSkiwNKoa3k0/Lq2MIdlZYoosd3wkM08 jIMBYrHNwAiGMdBJGNyPAkKiImcH1xZ9EuP6KaxFX1Y2w3yf/c7DD48dQlJ+RzRJ g+Kqk6O7vbU= =trir -----END PGP SIGNATURE----- --==_Exmh_1576564172_34200P-- --===============9018842972625439808== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --===============9018842972625439808==--