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 407FDC433F5 for ; Thu, 28 Apr 2022 14:26:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9DAF76B009A; Thu, 28 Apr 2022 10:26:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9896E6B009B; Thu, 28 Apr 2022 10:26:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 82ABA8D0001; Thu, 28 Apr 2022 10:26:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.26]) by kanga.kvack.org (Postfix) with ESMTP id 6D55D6B009A for ; Thu, 28 Apr 2022 10:26:37 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay11.hostedemail.com (Postfix) with ESMTP id 4251D8235F for ; Thu, 28 Apr 2022 14:26:37 +0000 (UTC) X-FDA: 79406513634.26.01F42ED Received: from mail-qk1-f181.google.com (mail-qk1-f181.google.com [209.85.222.181]) by imf22.hostedemail.com (Postfix) with ESMTP id C8195C0059 for ; Thu, 28 Apr 2022 14:26:35 +0000 (UTC) Received: by mail-qk1-f181.google.com with SMTP id i2so3696644qke.12 for ; Thu, 28 Apr 2022 07:26:36 -0700 (PDT) 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=k2xk0VfPUZZR4PgPEBFE7KbYEWH+FmFopnCFIlm7PdU=; b=BV94KuxAotFnCW2rpxR5ikP/WxESDoIazAhKPFkO1eGzDxo7hawOoKkHC0UbhoIeQy kZg8jfkxgeybcxSbVkPKyf/R8j319H1hEEjldKPErEBwufuhSw5mT4aclDQzGTGmOQ4z vfMoivqIpG4ELDuBcZ0Lo3UjNSF9EOuclEjFk4kMkAuHZnXHnZGbiU71bRjNAWpZoXdE OVtUxqBbeYfV85GYLzG9DEZSYCi7JYWgpRIAP4TxPtab35D28kaePo90gYcCyWnoTDSJ nh0zCTTwNRYmmxH3C3h+6DAcalHEbjnTNIOcg75fSF6dIHkflMcrL1mdWIN+kjqV2eZ+ euow== 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=k2xk0VfPUZZR4PgPEBFE7KbYEWH+FmFopnCFIlm7PdU=; b=z+/YmFRdCB+wYlLF1svnEZ4vjR2mlMr21pCe7CPKuUqJg7cjViO1FpZMXtLSwL0fiv pSTA2SDsHYjTpEsmG3oLIdTY9UBDETr/jbL0vH9fvfIQgG7vt77TN0jClbgZpL5fR0s/ 35N4re75EbN/SBTOaazGTcrrQc1WQT/aBD0CeWPTIzZ+ufRJB/yUUnlJLc8rGkAeV097 RZlMKDos1ZNcyykeGQrmAstNIHZQgAtHuhVtehlEPhcEwEoEAJSVIeL8ui4BG0XtVn6/ JjmvzV6V2+/JyuNHzGuabWvGlMI7SVpK69z982nw4RxF70RcTilh2l8vDxgZ2SVSd9F8 8HSg== X-Gm-Message-State: AOAM533lr6LMrbobEmelV86j8zQb0HplD5IxfmxdErY11a3qNU80N2e9 NCimUja+tDrCAME4RUXJDDx8cw== X-Google-Smtp-Source: ABdhPJxHZfOb9UMTvMfY0TOYnsyNy3pAynw8UhikG/kgqUZQDoSwCT+rqvbeUsQFKMN84pGDPsTDfQ== X-Received: by 2002:a05:620a:d85:b0:67b:a4:2036 with SMTP id q5-20020a05620a0d8500b0067b00a42036mr19369088qkl.112.1651155995814; Thu, 28 Apr 2022 07:26:35 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::1:d588]) by smtp.gmail.com with ESMTPSA id 21-20020ac85755000000b002f390bd8ac0sm84027qtx.53.2022.04.28.07.26.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Apr 2022 07:26:35 -0700 (PDT) Date: Thu, 28 Apr 2022 10:25:59 -0400 From: Johannes Weiner To: Minchan Kim Cc: Andrew Morton , Michal Hocko , Roman Gushchin , Shakeel Butt , Seth Jennings , Dan Streetman , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH 4/5] mm: zswap: add basic meminfo and vmstat coverage Message-ID: References: <20220427160016.144237-1-hannes@cmpxchg.org> <20220427160016.144237-5-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: C8195C0059 X-Stat-Signature: n7cuo9w9oyonrwqezshy9ts7xnrq7ogd Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=cmpxchg-org.20210112.gappssmtp.com header.s=20210112 header.b=BV94KuxA; dmarc=pass (policy=none) header.from=cmpxchg.org; spf=pass (imf22.hostedemail.com: domain of hannes@cmpxchg.org designates 209.85.222.181 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1651155995-802242 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: On Wed, Apr 27, 2022 at 03:16:48PM -0700, Minchan Kim wrote: > On Wed, Apr 27, 2022 at 05:20:29PM -0400, Johannes Weiner wrote: > > On Wed, Apr 27, 2022 at 01:29:34PM -0700, Minchan Kim wrote: > > > Hi Johannes, > > > > > > On Wed, Apr 27, 2022 at 12:00:15PM -0400, Johannes Weiner wrote: > > > > Currently it requires poking at debugfs to figure out the size and > > > > population of the zswap cache on a host. There are no counters for > > > > reads and writes against the cache. As a result, it's difficult to > > > > understand zswap behavior on production systems. > > > > > > > > Print zswap memory consumption and how many pages are zswapped out in > > > > /proc/meminfo. Count zswapouts and zswapins in /proc/vmstat. > > > > > > > > Signed-off-by: Johannes Weiner > > > > --- > > > > fs/proc/meminfo.c | 7 +++++++ > > > > include/linux/swap.h | 5 +++++ > > > > include/linux/vm_event_item.h | 4 ++++ > > > > mm/vmstat.c | 4 ++++ > > > > mm/zswap.c | 13 ++++++------- > > > > 5 files changed, 26 insertions(+), 7 deletions(-) > > > > > > > > diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c > > > > index 6fa761c9cc78..6e89f0e2fd20 100644 > > > > --- a/fs/proc/meminfo.c > > > > +++ b/fs/proc/meminfo.c > > > > @@ -86,6 +86,13 @@ static int meminfo_proc_show(struct seq_file *m, void *v) > > > > > > > > show_val_kb(m, "SwapTotal: ", i.totalswap); > > > > show_val_kb(m, "SwapFree: ", i.freeswap); > > > > +#ifdef CONFIG_ZSWAP > > > > + seq_printf(m, "Zswap: %8lu kB\n", > > > > + (unsigned long)(zswap_pool_total_size >> 10)); > > > > + seq_printf(m, "Zswapped: %8lu kB\n", > > > > + (unsigned long)atomic_read(&zswap_stored_pages) << > > > > + (PAGE_SHIFT - 10)); > > > > +#endif > > > > > > I agree it would be very handy to have the memory consumption in meminfo > > > > > > https://lore.kernel.org/all/YYwZXrL3Fu8%2FvLZw@google.com/ > > > > > > If we really go this Zswap only metric instead of general term > > > "Compressed", I'd like to post maybe "Zram:" with same reason > > > in this patchset. Do you think that's better idea instead of > > > introducing general term like "Compressed:" or something else? > > > > I'm fine with changing it to Compressed. If somebody cares about a > > more detailed breakdown, we can add Zswap, Zram subsets as needed. > > Thanks! Please consider ZSWPIN to rename more general term, too. That doesn't make sense to me. Zram is a swap backend, its traffic is accounted in PSWPIN/OUT. Zswap is a writeback cache on top of the swap backend. It has pages entering, refaulting, and being written back to the swap backend (PSWPOUT). A zswpout and a zramout are different things. > > From 8e9e2d6490b7082c41743fbdb9ffd2db4e3ce962 Mon Sep 17 00:00:00 2001 > > From: Johannes Weiner > > Date: Wed, 27 Apr 2022 17:15:15 -0400 > > Subject: [PATCH] mm: zswap: add basic meminfo and vmstat coverage fix fix > > > > Signed-off-by: Johannes Weiner Just for completeness, Nacked-by: Johannes Weiner > > @@ -87,7 +87,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v) > > show_val_kb(m, "SwapTotal: ", i.totalswap); > > show_val_kb(m, "SwapFree: ", i.freeswap); > > #ifdef CONFIG_ZSWAP > > - seq_printf(m, "Zswap: %8lu kB\n", > > + seq_printf(m, "Compressed: %8lu kB\n", > > (unsigned long)(zswap_pool_total_size >> 10)); > > seq_printf(m, "Zswapped: %8lu kB\n", > > (unsigned long)atomic_read(&zswap_stored_pages) << > > -- > > 2.35.3 > >