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 86203C433F5 for ; Tue, 11 Jan 2022 10:25:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237828AbiAKKZK (ORCPT ); Tue, 11 Jan 2022 05:25:10 -0500 Received: from shark4.inbox.lv ([194.152.32.84]:36826 "EHLO shark4.inbox.lv" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237737AbiAKKZJ (ORCPT ); Tue, 11 Jan 2022 05:25:09 -0500 Received: from shark4.inbox.lv (localhost [127.0.0.1]) by shark4-out.inbox.lv (Postfix) with ESMTP id CA769C01C2; Tue, 11 Jan 2022 12:25:05 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=inbox.lv; s=30062014; t=1641896705; bh=VRwkhrPflUcUAwu4sRDNMn5rSRlD5FjXnGFErmqRxs8=; h=Date:From:To:Subject:Message-ID:In-Reply-To:References: Content-Type:X-ESPOL:from:date; b=XR79L/Uygzf+mK1tEAn+kgVGjXvysfxJUNY3sSDQNZ69Fuqp8rWadpeFdNnKZDqhN YMrnnrLK/PvU5vUATpWqqjK1xP20CyFUcTrcWKEpkDzjHbS+nmjsgd5G94UpSdeokr 0KZ5MgsmBEtF0rZKxiHP8SB4FTLc9yxH+XbEBdTg= Received: from localhost (localhost [127.0.0.1]) by shark4-in.inbox.lv (Postfix) with ESMTP id BBAFEC0187; Tue, 11 Jan 2022 12:25:05 +0200 (EET) Received: from shark4.inbox.lv ([127.0.0.1]) by localhost (shark4.inbox.lv [127.0.0.1]) (spamfilter, port 35) with ESMTP id 5wbv1OlHIic4; Tue, 11 Jan 2022 12:25:05 +0200 (EET) Received: from mail.inbox.lv (pop1 [127.0.0.1]) by shark4-in.inbox.lv (Postfix) with ESMTP id 55137C00FC; Tue, 11 Jan 2022 12:25:05 +0200 (EET) Date: Tue, 11 Jan 2022 19:24:51 +0900 From: Alexey Avramov To: Yu Zhao Cc: Andrew Morton , Linus Torvalds , Andi Kleen , Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, page-reclaim@google.com, x86@kernel.org, hakavlad@gmail.com Subject: Re: [PATCH v6 0/9] Multigenerational LRU Framework Message-ID: <20220111192451.1a853019@mail.inbox.lv> In-Reply-To: <20220104202227.2903605-1-yuzhao@google.com> References: <20220104202227.2903605-1-yuzhao@google.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Virus-Scanned: OK X-ESPOL: AJ2EQ38cmnBBsMa9Lpgfme6kmZavNCkuvyHmvc49ixdFz9PMtNdrcW+QBYXxGwCl Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In some of my benchmarks MGLRU really gave unrivaled performance. I assume the adoption of MGLRU into the kernel would save billions of dollars and greatly reduce carbon dioxide emissions. However, there are also cases where MGLRU loses. There are cases where MGLRU does not achieve the performance that the classic LRU gives (at least I got such results when testing MGLRU before[1], but I did not report them here). As a Linux user, I would like to see both variants of LRU in the kernel, so that it is possible to switch to the suitable variant when needed: none of the LRU variants allowed me to squeeze the maximum for all cases. I hope to test MGLRU v6 later and show you some of its weaknesses and anomalies with specific logs and benchmarks. [1] I didn't have enough time and energy to decipher the results at that time: https://github.com/hakavlad/cache-tests/tree/main/mg-LRU-v3_vs_classic-LRU (but you can try to guess what it all means) 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 87362C433EF for ; Tue, 11 Jan 2022 10:26:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ScRwYe8wKMbPmY9XUsZiIdr7oeS967vXZvuWwDFdVL4=; b=j3VwJqh7Aw+TgD o2RHZuxYDFpFdirzxTz1ov3T+Tew61VaUtVr47O6Wtgmedl5Cq1z+TCDSkyDckeQjdshwmY4zkDud RxgBmMrwK0J4/NcK5pp0fMJNHV+jwexHeloZqp5MFvf5Wql7/Wc5ShLQOI3sRBHDtWZwpqqYbZG/2 MQqV4i+rHp+pTjW2+CmCx/Oy2Ydq5rqFZbvpxD4pQ0TeTx7mrzVzVjZzVRC1quJT+Dx0/XLiMoU94 mOzCvBliAgbOKpxK0mHTjGkgGkIMIOMb+7IxeGTtBnlOWLhfh2Y1K84Em3aE43iMKekhAifbKipod 5GYZhzv/cp2XBUOqSmzA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7EL4-00Fluo-EA; Tue, 11 Jan 2022 10:25:14 +0000 Received: from shark4.inbox.lv ([194.152.32.84]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7EKz-00FlsM-Kx for linux-arm-kernel@lists.infradead.org; Tue, 11 Jan 2022 10:25:11 +0000 Received: from shark4.inbox.lv (localhost [127.0.0.1]) by shark4-out.inbox.lv (Postfix) with ESMTP id CA769C01C2; Tue, 11 Jan 2022 12:25:05 +0200 (EET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=inbox.lv; s=30062014; t=1641896705; bh=VRwkhrPflUcUAwu4sRDNMn5rSRlD5FjXnGFErmqRxs8=; h=Date:From:To:Subject:Message-ID:In-Reply-To:References: Content-Type:X-ESPOL:from:date; b=XR79L/Uygzf+mK1tEAn+kgVGjXvysfxJUNY3sSDQNZ69Fuqp8rWadpeFdNnKZDqhN YMrnnrLK/PvU5vUATpWqqjK1xP20CyFUcTrcWKEpkDzjHbS+nmjsgd5G94UpSdeokr 0KZ5MgsmBEtF0rZKxiHP8SB4FTLc9yxH+XbEBdTg= Received: from localhost (localhost [127.0.0.1]) by shark4-in.inbox.lv (Postfix) with ESMTP id BBAFEC0187; Tue, 11 Jan 2022 12:25:05 +0200 (EET) Received: from shark4.inbox.lv ([127.0.0.1]) by localhost (shark4.inbox.lv [127.0.0.1]) (spamfilter, port 35) with ESMTP id 5wbv1OlHIic4; Tue, 11 Jan 2022 12:25:05 +0200 (EET) Received: from mail.inbox.lv (pop1 [127.0.0.1]) by shark4-in.inbox.lv (Postfix) with ESMTP id 55137C00FC; Tue, 11 Jan 2022 12:25:05 +0200 (EET) Date: Tue, 11 Jan 2022 19:24:51 +0900 From: Alexey Avramov To: Yu Zhao Cc: Andrew Morton , Linus Torvalds , Andi Kleen , Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, page-reclaim@google.com, x86@kernel.org, hakavlad@gmail.com Subject: Re: [PATCH v6 0/9] Multigenerational LRU Framework Message-ID: <20220111192451.1a853019@mail.inbox.lv> In-Reply-To: <20220104202227.2903605-1-yuzhao@google.com> References: <20220104202227.2903605-1-yuzhao@google.com> X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-Virus-Scanned: OK X-ESPOL: AJ2EQ38cmnBBsMa9Lpgfme6kmZavNCkuvyHmvc49ixdFz9PMtNdrcW+QBYXxGwCl X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220111_022509_867591_BD8ACA71 X-CRM114-Status: GOOD ( 10.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In some of my benchmarks MGLRU really gave unrivaled performance. I assume the adoption of MGLRU into the kernel would save billions of dollars and greatly reduce carbon dioxide emissions. However, there are also cases where MGLRU loses. There are cases where MGLRU does not achieve the performance that the classic LRU gives (at least I got such results when testing MGLRU before[1], but I did not report them here). As a Linux user, I would like to see both variants of LRU in the kernel, so that it is possible to switch to the suitable variant when needed: none of the LRU variants allowed me to squeeze the maximum for all cases. I hope to test MGLRU v6 later and show you some of its weaknesses and anomalies with specific logs and benchmarks. [1] I didn't have enough time and energy to decipher the results at that time: https://github.com/hakavlad/cache-tests/tree/main/mg-LRU-v3_vs_classic-LRU (but you can try to guess what it all means) _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel