From patchwork Thu Apr 13 05:57:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yang X-Patchwork-Id: 82822 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp823937vqo; Wed, 12 Apr 2023 23:28:59 -0700 (PDT) X-Google-Smtp-Source: AKy350aF0FH9Bvo+FBFANo8N3a6B1ZHEkrLchU60I/X9gO367uLMUsJQ4phduxY1j3lJi/IHvNl3 X-Received: by 2002:a17:902:d711:b0:1a1:cc0c:a5c2 with SMTP id w17-20020a170902d71100b001a1cc0ca5c2mr910991ply.62.1681367338864; Wed, 12 Apr 2023 23:28:58 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681367338; cv=none; d=google.com; s=arc-20160816; b=ioLl4Oqx0zWBybnwbzYyFmDb0mRh0G2T1wAcYCs+8xNuraQTXOp1bNAJ+2JiTZYtlz 4il1P4xEPQr22Q9Y9VeQAk2SsVQ41IDRhh4K6BEkZw/ypaHJpqtuLsnrUX/MsPaVhbCx dbwWkSjpQnc+AfkmXbFzTsEV8S3YfOhMKHfjJrF5Tib7igg+nd8H8HbHyFA03ZzPbtUH aAGiTxmgHtwfNR/KNsxkHREk3rH76qHzJ169XvzWRJ1uVn8mZ8TQ9TS1QknNJikR/C3n DqeMVNAhnCBNjUy+LCQ/vFsO0wQpp4OgJBRK05Q9J6qEAM56Cyf8Yv6L1xI0sQHahCqq NrCw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=EMaTR4sSlwAOx4WQ4M5tCj+DGTE+7Uk+KZavXgFEiS8=; b=L0PtldEr0I9+hvFBoxzo8kSpWiMcsAqWDL0jlqNc0MfvIWGyBuTd0DgXIFubmhP3S/ w49KrXaLh9KUaCDWaEV5r9zRwsQThIoHkcFs8yrCQAdRdnHcx+Sm3AtipPSiiA5wJ8xR v+3ta8laz3DyIitLu2BhVSPVUI8iBlEAs3sNoiV9UI6NZFm+58rBSosVnTy2y4pFhLOF EaMKLC+Er9M9oLLaPHbqQYEfS9k2NmzHmv8kh1htPZvd+/lkUYIYeyLz2waaKsoFRT0N tkINSmb+1bPu1ERVpTIBBKtQb5XTdnN23Ot0c8NJj8wGKvKoqqhlXVdFEeyWCCisbVIC SI0Q== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=zte.com.cn Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id b15-20020a170902b60f00b001a51cc721b8si1175551pls.327.2023.04.12.23.28.47; Wed, 12 Apr 2023 23:28:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=zte.com.cn Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229713AbjDMF6F (ORCPT + 99 others); Thu, 13 Apr 2023 01:58:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229484AbjDMF6D (ORCPT ); Thu, 13 Apr 2023 01:58:03 -0400 Received: from ubuntu20 (unknown [193.203.214.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42D86212C for ; Wed, 12 Apr 2023 22:58:02 -0700 (PDT) Received: by ubuntu20 (Postfix, from userid 1003) id E73CFE1A31; Thu, 13 Apr 2023 05:58:00 +0000 (UTC) From: Yang Yang To: akpm@linux-foundation.org, david@redhat.com Cc: yang.yang29@zte.com.cn, imbrenda@linux.ibm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ran.xiaokai@zte.com.cn, xu.xin.sc@gmail.com, xu.xin16@zte.com.cn, Jiang Xuexin Subject: [PATCH v7 5/6] ksm: update the calculation of KSM profit Date: Thu, 13 Apr 2023 13:57:59 +0800 Message-Id: <20230413055759.181210-1-yang.yang29@zte.com.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <202304131346489021903@zte.com.cn> References: <202304131346489021903@zte.com.cn> MIME-Version: 1.0 X-Spam-Status: No, score=3.4 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,FSL_HELO_NON_FQDN_1, HEADER_FROM_DIFFERENT_DOMAINS,HELO_NO_DOMAIN,NO_DNS_FOR_FROM, RCVD_IN_PBL,RDNS_NONE,SPF_SOFTFAIL,SPOOFED_FREEMAIL_NO_RDNS autolearn=no autolearn_force=no version=3.4.6 X-Spam-Level: *** X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1763041438623296676?= X-GMAIL-MSGID: =?utf-8?q?1763041438623296676?= From: xu xin When use_zero_pages is enabled, the calculation of ksm profit is not correct because ksm zero pages is not counted in. So update the calculation of KSM profit including the documentation. Signed-off-by: xu xin Cc: Xiaokai Ran Cc: Yang Yang Cc: Jiang Xuexin Cc: Claudio Imbrenda Cc: David Hildenbrand --- Documentation/admin-guide/mm/ksm.rst | 18 +++++++++++------- mm/ksm.c | 5 +++++ 2 files changed, 16 insertions(+), 7 deletions(-) diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst index 64e6a13bda74..1a0f623cd570 100644 --- a/Documentation/admin-guide/mm/ksm.rst +++ b/Documentation/admin-guide/mm/ksm.rst @@ -243,21 +243,25 @@ several times, which are unprofitable memory consumed. 1) How to determine whether KSM save memory or consume memory in system-wide range? Here is a simple approximate calculation for reference:: - general_profit =~ pages_sharing * sizeof(page) - (all_rmap_items) * + general_profit =~ ksm_saved_pages * sizeof(page) - (all_rmap_items) * sizeof(rmap_item); - where all_rmap_items can be easily obtained by summing ``pages_sharing``, - ``pages_shared``, ``pages_unshared`` and ``pages_volatile``. + where ksm_saved_pages equals to the sum of ``pages_sharing`` + + ``ksm_zero_pages`` of the system, and all_rmap_items can be easily + obtained by summing ``pages_sharing``, ``pages_shared``, ``pages_unshared`` + and ``pages_volatile``. 2) The KSM profit inner a single process can be similarly obtained by the following approximate calculation:: - process_profit =~ ksm_merging_pages * sizeof(page) - + process_profit =~ ksm_saved_pages * sizeof(page) - ksm_rmap_items * sizeof(rmap_item). - where ksm_merging_pages is shown under the directory ``/proc//``, - and ksm_rmap_items is shown in ``/proc//ksm_stat``. The process profit - is also shown in ``/proc//ksm_stat`` as ksm_process_profit. + where ksm_saved_pages equals to the sum of ``ksm_merging_pages`` and + ``ksm_zero_pages``, both of which are shown under the directory + ``/proc//``, and ksm_rmap_items is shown in ``/proc//ksm_stat``. + The process profit is also shown in ``/proc//ksm_stat`` as + ksm_process_profit. From the perspective of application, a high ratio of ``ksm_rmap_items`` to ``ksm_merging_pages`` means a bad madvise-applied policy, so developers or diff --git a/mm/ksm.c b/mm/ksm.c index 7867fae3c61c..10902c8c503f 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2936,8 +2936,13 @@ static void wait_while_offlining(void) #ifdef CONFIG_PROC_FS long ksm_process_profit(struct mm_struct *mm) { +#ifdef CONFIG_KSM_ZERO_PAGES_TRACK + return (long)(mm->ksm_merging_pages + mm->ksm_zero_pages) * PAGE_SIZE - + mm->ksm_rmap_items * sizeof(struct ksm_rmap_item); +#else return (long)mm->ksm_merging_pages * PAGE_SIZE - mm->ksm_rmap_items * sizeof(struct ksm_rmap_item); +#endif } /* Return merge type name as string. */