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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10BFCC433EF for ; Tue, 23 Nov 2021 13:20:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237157AbhKWNXN (ORCPT ); Tue, 23 Nov 2021 08:23:13 -0500 Received: from out30-44.freemail.mail.aliyun.com ([115.124.30.44]:39465 "EHLO out30-44.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237223AbhKWNXL (ORCPT ); Tue, 23 Nov 2021 08:23:11 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R261e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04400;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0UxzBImG_1637673599; Received: from 30.32.124.111(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0UxzBImG_1637673599) by smtp.aliyun-inc.com(127.0.0.1); Tue, 23 Nov 2021 21:20:00 +0800 Message-ID: <399f9ef5-3a77-902a-7b4c-86020e629944@linux.alibaba.com> Date: Tue, 23 Nov 2021 21:20:47 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.3.0 Subject: Re: [RFC PATCH] mm: Promote slow memory in advance to improve performance To: Yang Shi , Mel Gorman Cc: Andrew Morton , Huang Ying , Dave Hansen , Zi Yan , zhongjiang-ali@linux.alibaba.com, Xunlei Pang , Linux MM , Linux Kernel Mailing List References: From: Baolin Wang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/11/23 3:34, Yang Shi wrote: > On Mon, Nov 22, 2021 at 2:22 AM Baolin Wang > wrote: >> >> Some workloads access a set of data entities will follow the data locality, >> also known as locality of reference, which means the probability of accessing >> some data soon after some nearby data has been accessed. >> >> On some systems with different memory types, which will rely on the numa >> balancing to promote slow hot memory to fast memory to improve performance. >> So we can promote several sequential pages on slow memory at one time >> according to the data locality for some workloads to improve the performance. > > Fault around for NUMA fault definitely could reduce the overhead for > NUMA balancing by having fewer faults. I think this could be extended > to regular NUMA balancing too. But I'm not sure whether false > positives are worth concerning or not. OK. Like Huang Ying said, maybe we can add some algorithm to adjust the window of proactive numa faults dynamically. Thanks for your input. > > I recall Mel proposed fault around too (not in patch, but shared some > ideas). Added Mel in this thread.