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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 2A6F4C433DB for ; Fri, 12 Mar 2021 14:43:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3297E64FA7 for ; Fri, 12 Mar 2021 14:43:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3297E64FA7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=flapflap.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B9E6E8D0367; Fri, 12 Mar 2021 09:43:36 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B4D978D0361; Fri, 12 Mar 2021 09:43:36 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A15808D0367; Fri, 12 Mar 2021 09:43:36 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0122.hostedemail.com [216.40.44.122]) by kanga.kvack.org (Postfix) with ESMTP id 843228D0361 for ; Fri, 12 Mar 2021 09:43:36 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 3CD838248D7C for ; Fri, 12 Mar 2021 14:43:36 +0000 (UTC) X-FDA: 77911490832.28.2324C0D Received: from server02.webapps.manitu.net (server02.webapps.manitu.net [217.11.48.34]) by imf25.hostedemail.com (Postfix) with ESMTP id 5274F6000104 for ; Fri, 12 Mar 2021 14:43:33 +0000 (UTC) Received: from webmail.manitu.de (localhost [127.0.0.1]) by server02.webapps.manitu.net (Postfix) with ESMTP id E737D660201 for ; Fri, 12 Mar 2021 15:43:33 +0100 (CET) MIME-Version: 1.0 Date: Fri, 12 Mar 2021 15:43:33 +0100 From: Peter Weber To: linux-mm@kvack.org Subject: Is anonymous memory part of the page cache on Linux? User-Agent: Roundcube Webmail/1.4.11 Message-ID: X-Sender: peter.weber@flapflap.eu Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-manitu-Webmail-Sender: cHdlYmVyQGZsYXBmbGFwLmV1 X-Stat-Signature: unb67hok9du8zrzdiiouyk7p6wt495t3 X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 5274F6000104 Received-SPF: none (flapflap.eu>: No applicable sender policy available) receiver=imf25; identity=mailfrom; envelope-from=""; helo=server02.webapps.manitu.net; client-ip=217.11.48.34 X-HE-DKIM-Result: none/none X-HE-Tag: 1615560213-637788 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hello! Hopefully I'm asking here in the right place and don't disturb. Is anonymous memory - i.e. program heap and stack - part of the page cache on Linux? The documentation[1] of the kernel does not state that. But the Wikipedia entry about page cache contains a graphic[2] (look at the top right) which gives me the impression that 'malloc()' allocates dynamic memory within the page cache. Is it possible that the page cache serves as general foundation for memory management on Linux? Taking into account that `mmap()` also allows for anonymous mappings this could fit together? I've asked this originally on Stackoverflow[3]. Thank you Peter [1] https://www.kernel.org/doc/html/latest/admin-guide/mm/concepts.html#anonymous-memory [2] https://en.wikipedia.org/wiki/Page_cache#/media/File:The_Linux_Storage_Stack_Diagram.svg [3] https://stackoverflow.com/q/66587345/1054324