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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E053BC433EF for ; Mon, 4 Oct 2021 11:39:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD9A56120D for ; Mon, 4 Oct 2021 11:39:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233034AbhJDLlh (ORCPT ); Mon, 4 Oct 2021 07:41:37 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:41946 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230200AbhJDLlg (ORCPT ); Mon, 4 Oct 2021 07:41:36 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 888F4222EF; Mon, 4 Oct 2021 11:39:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1633347586; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nT/jLfbNhArcPOADaW8wlcm8on7ZVbyGnGG2HoqjWGs=; b=NxCm1A1BFyPVegRtNI1alewKpJJ93UlMPsXG2s1Y55+FsrrUc0z3At7XULFaLblu2QDBe4 Lc3+z0Nyuk2kXWdUTtlo3yHHlV+2gPlNcyV7e4kE3DNhjY+j2Nz6eNlg7EqOJzAEFmBlS0 hY4V/gg43d3R/9bQc1oad3MIcViQsjc= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1633347586; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nT/jLfbNhArcPOADaW8wlcm8on7ZVbyGnGG2HoqjWGs=; b=ku7g04Hn//qUxif9ptrSCqNlDhQnftU/FVmX/OEzkXi51CghUtYI3oZPysk7CGpLKAREUE B3vRE0HcbofNcuCw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id B07E51348D; Mon, 4 Oct 2021 11:39:20 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id crpgKujnWmFaBwAAMHmgww (envelope-from ); Mon, 04 Oct 2021 11:39:20 +0000 Message-ID: <075fde61-8c28-25ec-0ec1-28b1bdea7c95@suse.cz> Date: Mon, 4 Oct 2021 13:39:46 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.0.3 Subject: Re: [QUESTION] is SLAB considered legacy and deprecated? Content-Language: en-US To: Hyeonggon Yoo <42.hyeyoo@gmail.com>, David Rientjes Cc: linux-mm@kvack.org, Christoph Lameter , Pekka Enberg , Joonsoo Kim , Andrew Morton , linux-kernel@vger.kernel.org References: <20210927090347.GA2533@linux.asia-northeast3-a.c.our-ratio-313919.internal> <8aa15f4b-71de-5283-5ebc-d8d1a323473d@suse.cz> <20210928111231.GA2596@linux.asia-northeast3-a.c.our-ratio-313919.internal> <20211003055928.GA7643@linux.asia-northeast3-a.c.our-ratio-313919.internal> <377a622-9a5e-37dc-8f8d-42ae124042b6@google.com> <20211004060109.GA2949@linux.asia-northeast3-a.c.our-ratio-313919.internal> From: Vlastimil Babka In-Reply-To: <20211004060109.GA2949@linux.asia-northeast3-a.c.our-ratio-313919.internal> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/4/21 08:01, Hyeonggon Yoo wrote: > On Sun, Oct 03, 2021 at 06:25:29PM -0700, David Rientjes wrote: >> I would disagree that SLAB isn't currently maintained, I think it's >> actively maintained. > > I thought it was not actively maintained because most of patches were > fixups and cleanups for years and as Vlastimil said, new features are Fixups and cleanups still count as "actively maintained". The opposite case would be "nobody uses it because it was broken for years since commit X and we only noticed now". > only added to SLUB. development was focused on SLUB. > >> I think the general guidance is that changes for both allocators can still >> be merged upstream if they show a significant win (improved performnace, >> maintaining performance while reducing memory footprint, code hygiene, >> etc) and there's no specific policy that we cannot make changes to >> mm/slab.c. > > Good. > > I see things to improve in SLAB and want to improve it. > I will appreciate if you review them. It would be great if your motivation started with "I prefer SLAB over SLUB because X and Y but I need to improve Z", not just a theoretical concern. > Thanks, > Hyeonggon >