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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55290C433FE for ; Mon, 7 Feb 2022 17:56:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343497AbiBGRym (ORCPT ); Mon, 7 Feb 2022 12:54:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239410AbiBGRtR (ORCPT ); Mon, 7 Feb 2022 12:49:17 -0500 Received: from mail-qv1-xf35.google.com (mail-qv1-xf35.google.com [IPv6:2607:f8b0:4864:20::f35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFC8CC0401D9 for ; Mon, 7 Feb 2022 09:49:16 -0800 (PST) Received: by mail-qv1-xf35.google.com with SMTP id k4so11959757qvt.6 for ; Mon, 07 Feb 2022 09:49:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=kJucW2FhnAmOVXK6ttAIBgemWe7fm9oO1NBHaN+SpLo=; b=7t3DM3VcFauVZOBlngQ9606Z9gD+sKLDq4AgAEevZr3ZavsH+WJjWgzundrmQ8j/fH hCffawc1iSxT+eaqadAZ1tqlVNTDb+A8KjFDmVKplNkHqDhpdrPs8wFr6OC0CiykGHfz AAKSENzVQE2vrUQ/ZlKTDOUsfDlVmSnj8w3uUXoD6Bbh5yOayLCi6VyiOjsv2oE4naa5 MzMyXm98/uP0z8aA1/Qe3tZBOtjj8qSrjwkLFmZTgROZ7VSP+wkCsFASes3w87WNcxdo jYbbZnyI+uLZXYUYlcOT73zPchwbG85kEXuSM8Hr9RZ6VbhoEm2EuodTvRrGz/h2HdJ4 n6tQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=kJucW2FhnAmOVXK6ttAIBgemWe7fm9oO1NBHaN+SpLo=; b=MHfvvAEjJEOq9PBEATNoqa7h69OAxHVIRPB3cup41g0kAQpGV+Q/5vRiVpsKPe7LK5 xuWj8IC0HRNx4P6UYwjoloLTZNPzGRc1DkjoZyEzBSIuC0+XZw4hczU2uPvxkrUyk7CD Wwy0PCp4Y8AcTeEnHn8ki+oNMLtNq6PvZx5iA41ByZjma/f1oMpcThuyz0NM/TWB9XOb E+7TVjxTVrK4PAx/qywTGlRUn6pGaT7MUACRai/9WUfvEaSX4x/G3oQG24YqgeOfQuCS /gU2/eyWaTJN2At3l/A93pgljDntgLz+Kf/NMQvhv5Ri4BzdqfqL2jWPjzgihhqvsJzT shuQ== X-Gm-Message-State: AOAM5327ob7YWEzuEgwGjJVl99DXjI4JxnmjBtxuFIAPI0xD4Bc5SA9A PyCIyFHDYfm2Z/XmZAKZ2GVTGA== X-Google-Smtp-Source: ABdhPJyfrQtt982KQJ8YVomy4l18OH5G1tRs6T70oQ9tcGHf4td1lFkXstlwrfw1W6P49W2p7bCKGw== X-Received: by 2002:a05:6214:29e2:: with SMTP id jv2mr600877qvb.4.1644256156176; Mon, 07 Feb 2022 09:49:16 -0800 (PST) Received: from localhost (cpe-98-15-154-102.hvc.res.rr.com. [98.15.154.102]) by smtp.gmail.com with ESMTPSA id s28sm5387928qkm.53.2022.02.07.09.49.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Feb 2022 09:49:15 -0800 (PST) Date: Mon, 7 Feb 2022 12:49:15 -0500 From: Johannes Weiner To: Huang Ying Cc: Peter Zijlstra , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Feng Tang , Dave Hansen , Baolin Wang , Andrew Morton , Michal Hocko , Rik van Riel , Mel Gorman , Yang Shi , Zi Yan , Wei Xu , osalvador , Shakeel Butt , zhongjiang-ali Subject: Re: [PATCH -V11 3/3] memory tiering: skip to scan fast memory Message-ID: References: <20220128082751.593478-1-ying.huang@intel.com> <20220128082751.593478-4-ying.huang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220128082751.593478-4-ying.huang@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 28, 2022 at 04:27:51PM +0800, Huang Ying wrote: > If the NUMA balancing isn't used to optimize the page placement among > sockets but only among memory types, the hot pages in the fast memory > node couldn't be migrated (promoted) to anywhere. So it's unnecessary > to scan the pages in the fast memory node via changing their PTE/PMD > mapping to be PROT_NONE. So that the page faults could be avoided > too. > > In the test, if only the memory tiering NUMA balancing mode is enabled, the > number of the NUMA balancing hint faults for the DRAM node is reduced to > almost 0 with the patch. While the benchmark score doesn't change > visibly. > > Signed-off-by: "Huang, Ying" > Suggested-by: Dave Hansen > Tested-by: Baolin Wang > Reviewed-by: Baolin Wang > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Rik van Riel > Cc: Mel Gorman > Cc: Peter Zijlstra > Cc: Yang Shi > Cc: Zi Yan > Cc: Wei Xu > Cc: osalvador > Cc: Shakeel Butt > Cc: zhongjiang-ali > Cc: linux-kernel@vger.kernel.org > Cc: linux-mm@kvack.org Looks good to me. Acked-by: Johannes Weiner