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 1D9E9C3600C for ; Thu, 3 Apr 2025 21:54:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6D003280004; Thu, 3 Apr 2025 17:54:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 68237280001; Thu, 3 Apr 2025 17:54:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 54AC8280004; Thu, 3 Apr 2025 17:54:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 35FC0280001 for ; Thu, 3 Apr 2025 17:54:14 -0400 (EDT) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id A02BF1212DB for ; Thu, 3 Apr 2025 21:54:14 +0000 (UTC) X-FDA: 83294086428.14.0BFE1F8 Received: from mail-qv1-f51.google.com (mail-qv1-f51.google.com [209.85.219.51]) by imf09.hostedemail.com (Postfix) with ESMTP id C4148140008 for ; Thu, 3 Apr 2025 21:54:12 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=jr6K2WGU; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf09.hostedemail.com: domain of nphamcs@gmail.com designates 209.85.219.51 as permitted sender) smtp.mailfrom=nphamcs@gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1743717252; a=rsa-sha256; cv=none; b=h1KdPuzp9HmRDRfIWQedWyGlI236lz8q97Edny5QsGW2GdCEgMjM13p8btOiY/6WGXhDm+ bMn6U5DWtgjfem8VqZiGn79X2wvUUsuVhIhgicREfLg1OcV0H5Tw2ZgpzODu+SKpYKxnen C38Ws6320Wte9OwHuvXeoD/AdbuRCBQ= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=jr6K2WGU; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf09.hostedemail.com: domain of nphamcs@gmail.com designates 209.85.219.51 as permitted sender) smtp.mailfrom=nphamcs@gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1743717252; h=from:from:sender:reply-to:subject:subject: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:dkim-signature; bh=88Axpm7x8Xr7dH3zH64884UsH9qBE9Od9jKWl8HY7l4=; b=voDyy6wZRe5DGihEDKzoNiIkRQlL2MdzLWctnfSBtD7bnYhE5XYxA+svDkt6zPhdLfbVoN RulEtQ+Tdi+04Z66DGD/WcWv8ZrpFnCvmmnnViWumlfFGbHew3ov8kKUk0/hu+zxRSXH+b CQSBIVNrY2+Itqwtsfxn2sN1NfZctwY= Received: by mail-qv1-f51.google.com with SMTP id 6a1803df08f44-6e8fc176825so12071866d6.0 for ; Thu, 03 Apr 2025 14:54:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1743717252; x=1744322052; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=88Axpm7x8Xr7dH3zH64884UsH9qBE9Od9jKWl8HY7l4=; b=jr6K2WGUnfA7VrsUCa52qfVDdk61NWQcBw8lIIeH79ukOqMX4VWRGhgKzaBSmHdJ+m fQi7hN9NqnM49uWsUy+dmWxQZmLt3N10mAv9be6YTMcQOqXVJmOYaLo3GsrrGL2RuZEk 4RkDzPKuE11BiD5N8auCSVKKrq3Bj/jbimwP9h2dSQgRKj6y4DVzZMyGO1+mkolRX+Ki 4r5vdyfw41A56ndwIFTlowrGrrF5RbpM40re0ajWN7HViRNRfNA/iQm9KWjGlojDyt/s 9lHgC7n+5Ce9ul8S7DemiJvDIfNKBulVx1CwrMltx+H2T4LHP3Afz5VY9RL5gTmZuIvm wCaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1743717252; x=1744322052; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=88Axpm7x8Xr7dH3zH64884UsH9qBE9Od9jKWl8HY7l4=; b=MPXCY7x5Q6HbzGPgJn3jkUFm5UfxVj4XEMopN7YM0jUcbAe9Uv+hFUJoONBtHwyp+U 5AMwny/mnYNWF6tZ+DtmGQFAhnXEbc2h+fo/0qY2+luow48J1QJGwrsdFUQ9ppf2y+tO aOVI7BjCqVB3zbIVGvjwjJ6sSHBnDZOTn0dXz4uLa27y7rJu9QPeA87F6fCr8jmB3TjU alr8s4eRAIxULDa9sDn5cZng4x7946Cj9wMGrlA4o34txR3FDma4I4URoAthmXKJlmuC IbFEkPSKmp9NM9H/L/HaqeYkjGddGGycyCoGwjHH1YJEXMwzUuUA4QhbKJzBcpv5gplh 855g== X-Forwarded-Encrypted: i=1; AJvYcCVupyo9fPBoPYwdpXJSeVzwfMikg9DWG2EfpU3jj/5zOSIcZkLfzAhmWOxtKZ9MAtX8bCkA+wnh0w==@kvack.org X-Gm-Message-State: AOJu0YyMvU9QiaCf7cQalSzAnI2zbz+4sbYKWiuzVEUN0y8Dq9wyKHPD kbXIqPISrTLGaMfQlFif3rgo4gz7rUmuJllc/nSV0hrwE5KgynAUDpvec5+YX/OAh40Fyxd4M/b aPzttXpUErsCNaoMBVTGa9B7ZoLw= X-Gm-Gg: ASbGncszNvwZt6XrSg/1fh2pI52Z8Vea7tB2v9RNMvrBAPbNEwI4m+r5lEpmLqB5LuS z8A1yBLEYe4LwMHBh2DvJ64flzsT1KJXHyRjlp4oHf6FijJvCa71HJSU+bSJWx0/PvuYrWmLCk2 tRuEl+QoefU6xOVuBK80dVrqGPpyVH5ooZz579vu2nhQ== X-Google-Smtp-Source: AGHT+IHWA/DTTo/wy0BoR2/2DT3q6Qni8aVAJdaZLs908lG+vvidEC1SNEI9NdZni4AWp0AKP9D6KMZ1bh9dFPiX9ys= X-Received: by 2002:a05:6214:246d:b0:6e8:fb8c:e6dd with SMTP id 6a1803df08f44-6f00de6a59amr13972126d6.5.1743717251789; Thu, 03 Apr 2025 14:54:11 -0700 (PDT) MIME-Version: 1.0 References: <20250401171754.2686501-1-vitaly.wool@konsulko.se> <6d5ed99eb91c5d13b8c16dde6f8df4d9@beldev.am> In-Reply-To: <6d5ed99eb91c5d13b8c16dde6f8df4d9@beldev.am> From: Nhat Pham Date: Thu, 3 Apr 2025 14:54:00 -0700 X-Gm-Features: ATxdqUFcdSRub8tFmPzgz5K52IXVo277YAPCKRkb0Jrr2BCVdnntRtynWw9Gi6I Message-ID: Subject: Re: [PATCH] mm: add zblock allocator To: igor.b@beldev.am Cc: Shakeel Butt , Vitaly Wool , linux-mm@kvack.org, akpm@linux-foundation.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: C4148140008 X-Stat-Signature: wtddy5zmyhjopwbzah5cfj7gfh4p7zts X-HE-Tag: 1743717252-136547 X-HE-Meta: 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 M+DUXke6 nvINF5mBC6J/6ZwviwADohUFzvBz9mftTlDTPR6XousttpshHbL8hiG+/a1twK723s7s7+gx/Ug19eQ5G//o7djf2X8QB0xlYeTlZCyRDxR01ExTB5tY3oHr+hxeKeEaqTMUbIKXPp6pafkGmHSchQyPPorutf+g4RlSnIgvlAHC8YntQBZJcveQIFxPOY1MMJn9Gb0E4L7uI4j9+G8aYFcF+RUMq3xIE9rPFZVZscd3/AMGY8EZa+kwBJYQphZcrkny2m0m82uPH32MjntP3ACQv8L1ydVqJmDQsmYU83LYkHZYTNgCP2d3DzHUR1Nx+tNoY 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: List-Subscribe: List-Unsubscribe: On Tue, Apr 1, 2025 at 11:45=E2=80=AFPM wrote: > > Hi Shakeel, > > 2025-04-02 03:16 Shakeel Butt wrote: > > Hi Vitaly, > > > > On Tue, Apr 01, 2025 at 07:17:54PM +0200, Vitaly Wool wrote: > >> zblock is a special purpose allocator for storing compressed pages. > >> It stores integer number of compressed objects per its block. These > >> blocks consist of several physical pages (2**n, i. e. 1/2/4/8). > >> > >> With zblock, it is possible to densely arrange objects of various > >> sizes > >> resulting in low internal fragmentation. Also this allocator tries to > >> fill incomplete blocks instead of adding new ones, in many cases > >> providing a compression ratio substantially higher than z3fold and > >> zbud > >> (though lower than zmalloc's). > >> > >> zblock does not require MMU > > > > Can you explain why not requiring MMU is important for your use-case? > > Also what exactly is your use-case? Are you planning to use zblock > > through zram or zswap or something new? > > We have 2 use cases for a zpool backend: data centers (zswap) and small > MMU less devices, this is where zram comes ito play. We know that zram > over zpool patch is still out of tree but we also know the story behind > that :) In the upstream tree, zram also depends on MMU. It is probably different in your private tree, but please keep the conversation and documentation aligned with the reality of upstream :)