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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6925EC433EF for ; Tue, 26 Apr 2022 07:27:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D2C556B0074; Tue, 26 Apr 2022 03:27:04 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CDAFE6B0075; Tue, 26 Apr 2022 03:27:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BA3946B0078; Tue, 26 Apr 2022 03:27:04 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.26]) by kanga.kvack.org (Postfix) with ESMTP id ACD126B0074 for ; Tue, 26 Apr 2022 03:27:04 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id 8430C6047E for ; Tue, 26 Apr 2022 07:27:04 +0000 (UTC) X-FDA: 79398198768.16.265E6AB Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf30.hostedemail.com (Postfix) with ESMTP id 4D24480056 for ; Tue, 26 Apr 2022 07:26:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1650958023; x=1682494023; h=message-id:subject:from:to:cc:date:in-reply-to: references:mime-version:content-transfer-encoding; bh=jaNEaOZHZW4ArX88xjysMT3Bv8oI1VDPlRS5BXJ1sXs=; b=FFl7yd8X+4aOMa5PxPn5uYlDfAR9PDk6mLaAfzTdMmqzF4JKYKHEmuZX 4H3dpfyezorgdgoqjuztNcvl7rzWgYPeQXXCQKF2PLxm/kpCaBpIgxv9y PKlcDrDzEn/Jw/X0lU4zq+coJigzJb5PWdq22DYyCE0kzK41xCEePzTa5 D+OaavJy2y9JebpdIXb8P0X8RUkF5v2RLRqaQ7stUZY5/lcP/PONa6la8 ZqX0mMaJfvwu2KqPTJ3SvJs4WB9adDj4XX5Vj6IXrB3DlTsUZ9d0ZARsz lg2M5/N01pCe81gkCC6Ce44OK/QVOHJJJWIuE7FdjjStOqui5y7ijcFR+ A==; X-IronPort-AV: E=McAfee;i="6400,9594,10328"; a="290624933" X-IronPort-AV: E=Sophos;i="5.90,290,1643702400"; d="scan'208";a="290624933" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Apr 2022 00:27:02 -0700 X-IronPort-AV: E=Sophos;i="5.90,290,1643702400"; d="scan'208";a="558161318" Received: from yyu16-mobl.ccr.corp.intel.com ([10.254.212.128]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Apr 2022 00:26:59 -0700 Message-ID: <9581e4acc5392fd3f173189f7bd3ed11c372883e.camel@intel.com> Subject: Re: [PATCH v3 1/7] mm: demotion: Fix demotion targets sharing among sources From: "ying.huang@intel.com" To: Jagdish Gediya Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, baolin.wang@linux.alibaba.com, dave.hansen@linux.intel.com, aneesh.kumar@linux.ibm.com, shy828301@gmail.com, weixugc@google.com, gthelen@google.com, dan.j.williams@intel.com Date: Tue, 26 Apr 2022 15:26:56 +0800 In-Reply-To: References: <20220422195516.10769-1-jvgediya@linux.ibm.com> <20220422195516.10769-2-jvgediya@linux.ibm.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.3-1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 4D24480056 X-Stat-Signature: 19wf51fw1j3w78yfniptwsxa5unoj6eu X-Rspam-User: Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=FFl7yd8X; spf=none (imf30.hostedemail.com: domain of ying.huang@intel.com has no SPF policy when checking 192.55.52.88) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com X-Rspamd-Server: rspam09 X-HE-Tag: 1650958017-130372 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: On Mon, 2022-04-25 at 15:02 +0530, Jagdish Gediya wrote: > On Sun, Apr 24, 2022 at 11:25:50AM +0800, ying.huang@intel.com wrote: > > > Subject: [PATCH v3 1/7] mm: demotion: Fix demotion targets sharing among sources > > > > IMHO, this patch doesn't fix some bugs in the original code. Instead, > > it just enhances the original code. For example, the subject could be, > > I think it is fixing a bug, there is a comment in the code which > mentions that 'used_targets will become unavailable in future passes. > This limits some opportunities for multiple source nodes to share a > destination'. As per this comment, it was intended to share a node as > demotion targets with some limits but the code limits not some but all > such opportunities as no common node can be demotion targets for > multiple source node as per current code. IMHO, the original code is just to keep as simple as possible to address the issue for the real machines at that time. That provides a base line for future improvement like you have done. If the original code wouldn't work well for the target machines, then we fixed a bug. But if that doen't work well for some new kind of machines, then we need to improve the code, add more feature, not to fix a bug. Best Regards, Huang, Ying > >   mm: demotion: support to share demotion targets among sources > > > > Best Regards, > > Huang, Ying > > > > [snip] > > > > > >