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 76542C433F5 for ; Thu, 5 May 2022 22:25:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1386254AbiEEW2s (ORCPT ); Thu, 5 May 2022 18:28:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46476 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351986AbiEEW2p (ORCPT ); Thu, 5 May 2022 18:28:45 -0400 Received: from mail-vs1-xe35.google.com (mail-vs1-xe35.google.com [IPv6:2607:f8b0:4864:20::e35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1618289AE for ; Thu, 5 May 2022 15:25:03 -0700 (PDT) Received: by mail-vs1-xe35.google.com with SMTP id y74so5532047vsy.7 for ; Thu, 05 May 2022 15:25:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ZTU61zGXmWFiJ96Frh3Jz27MZBWaPQRzBHvvGIgt+qo=; b=QZRowjxdyK3cW28/2AurA6uZk0guOaXUobYrDQoZCXWjvLQ/UqqjkspA5cq5vJ+lmO +3VbOyg8tu+9HHC1yNMS9fsG78gc0LDsxRKGKuxDPRLFtxvfi6CwNOqKaTu2udwfQwkv kR9lBSbM5k/K8gXDLSshvj7HkXa/BzC0t91oaM4geJKTL/jxwdmyKz/neojgz/Uo6xaw AOiiQ8YF0qfzCUU3y/7/icQ5tkmKsKoBTJn5cIyN71HYj/JFEs9X81LOQVThWl5uXnKb 3HnpMtxMR/nY9nHCaG3a0wOMj9PnPQKa4DCx8yQwXiLEURUhuk9+smXGAN7Fyv6N/LU0 tzvw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ZTU61zGXmWFiJ96Frh3Jz27MZBWaPQRzBHvvGIgt+qo=; b=YL1FsyR0fthw9Qw0eUuVuPahSLDBimi0dVn8EM3QIcYvBh5Wd9Jm6o5erxecKF5lcU Btvk9Y17xCD2GWIvhQoYGBaZc3E2ihULSTQHG4CbwiMcjuEy8c0WQf09OND5X+b/0Hzq 6r6kvmNfvIHloCq7G3xqDAlBOhzMEedTN+YLAfqfagItb3zo4t7F/KjobnaclsMrXpv5 3UawTjLiFbpMWfFj8KY/DAURY4NzvC5ip6/9ULCqUS43vDeZD6Vm5tt/4YGSpW8L/omT rfYqfsIJmmdo+qlt/uV5my3xWLX0yhWozeI+HImJL2c74i9WzVhHq5FeR6xwEi1QtyIv aGmw== X-Gm-Message-State: AOAM531CyskKXd75z5ZC/doDqcLaVLxVkMWnNJS0wujGJPylnY04uZ3i D6X2ASV2ARLHyOav4h5+heFXG02Q5E3JA81FCKgnBw== X-Google-Smtp-Source: ABdhPJzSTIXaeYs3GBff5g8EE46n+pwTbaDmDqbFn++uI37hHmsvQXFL1UGe+27TlhuxLyn320oDrpT4/PNoNTSXYm8= X-Received: by 2002:a67:c29e:0:b0:32d:1090:54cb with SMTP id k30-20020a67c29e000000b0032d109054cbmr108667vsj.56.1651789502928; Thu, 05 May 2022 15:25:02 -0700 (PDT) MIME-Version: 1.0 References: <20220427160016.144237-1-hannes@cmpxchg.org> <20220427160016.144237-5-hannes@cmpxchg.org> In-Reply-To: From: Suleiman Souhlal Date: Fri, 6 May 2022 07:24:51 +0900 Message-ID: Subject: Re: [PATCH 4/5] mm: zswap: add basic meminfo and vmstat coverage To: Shakeel Butt Cc: Yang Shi , Johannes Weiner , Minchan Kim , Andrew Morton , Michal Hocko , Roman Gushchin , Seth Jennings , Dan Streetman , Linux MM , Cgroups , LKML , Kernel Team Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 6, 2022 at 4:33 AM Shakeel Butt wrote: > > On Thu, Apr 28, 2022 at 9:54 AM Yang Shi wrote: > > > [...] > > > Yes, we have some modifications to zswap to make it work without any > > > backing real swap. Though there is a future plan to move to zram > > > eventually. > > > > Interesting, if so why not just simply use zram? > > > > Historical reasons. When we started trying out the zswap, I think zram > was still in staging or not stable enough (Suleiman can give a better > answer). One of the reasons we chose zswap instead of zram is that zswap can reject pages. Also, we wanted to have per-memcg pools, which zswap made much easier to do. -- Suleiman