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 4D169C4332F for ; Thu, 27 Jan 2022 15:42:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C0DE96B0089; Thu, 27 Jan 2022 10:42:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BBD766B008C; Thu, 27 Jan 2022 10:42:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AAC6F6B0093; Thu, 27 Jan 2022 10:42:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0162.hostedemail.com [216.40.44.162]) by kanga.kvack.org (Postfix) with ESMTP id 9CBF66B0089 for ; Thu, 27 Jan 2022 10:42:06 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 5F4AA92EBE for ; Thu, 27 Jan 2022 15:42:06 +0000 (UTC) X-FDA: 79076483052.05.64FB797 Received: from mail-lf1-f51.google.com (mail-lf1-f51.google.com [209.85.167.51]) by imf01.hostedemail.com (Postfix) with ESMTP id 7FBBA40008 for ; Thu, 27 Jan 2022 15:42:05 +0000 (UTC) Received: by mail-lf1-f51.google.com with SMTP id x23so6269627lfc.0 for ; Thu, 27 Jan 2022 07:42:05 -0800 (PST) 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=MfyhRIJpExvB5oLC8bK80nt6dS7pKQKJ+WzxTeqwLMk=; b=mzVnI9hpBJqoZJb51BXe/CTWQy7ox1o88fNB47TS3//euJpqZI/oivu1J7IB1UFWJP 43TYlpPyn5VyOdkq010nfXCa3bNGsn0wh1gCCszlkBJCAVZ3ubVFoOpt3E+r7rn+auaK 2w5MnvjQLTtDjGio6q1lBH/9U+4XSff3eG3Pr6MewWoza3mxSjrM8r+e8NvxLKVs7o5a a0Yf3wcXOiUR0rxGU5yqKXXON8ovGUsQhYzKPTuEidVeUKN0/+tQRbr4ELQpUHcqdrVI RFcS7tS0Ezsvz/NHfuBCLFx8X5gUpNhK+yDzqpB2CKAeq8DygU/WUuogLlY0qnnZDNR2 eqfw== 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=MfyhRIJpExvB5oLC8bK80nt6dS7pKQKJ+WzxTeqwLMk=; b=dmcSB3N2LGGQtuTQnkf/50Pq8p+pZ47Eypi7OKDTRyr91Rzol8533Je8NMZd7Km8ma 9sxWfdzxuSiAj7uHUmNljUPfFUzrO9Rhn65x7H65xS7ZT0eeK+ic2i60bXOCPzF335kf TIlzjKlFRtWwi98GrN+ZWE2hYV6t3daq5n0MXsn06S/DIwCY9ZWMrKZIXw11niVfHT+h JPnpVOXJTFaICl/DSwRtfXFXzw/vNlRUEhDDOnYHIRiZ99xcKtDiVRZnBpicWjwzP14F V2tKtDfASlKryKy7Je+5hc2lRbvpKznKLYQUUpCTh7zIrzMi9EbAUgiJT/q4TSDIGiTt doHw== X-Gm-Message-State: AOAM531Gar4D21+rvFvfpbmJDQ+xsdV7cnpcsIC7UsCBhKB0vfpgbk23 LYIWgZK6mg+ixcUBragFtTg9NRCfZcaWa6scYUtrqw== X-Google-Smtp-Source: ABdhPJyHf+Jl4G149KcLmKjH0/4FJlFN3TGPnzzUNBugVy4tA4FH9JO8/yGxeymhQL/z3i9e+IhExPFRJaBplGbFCII= X-Received: by 2002:ac2:4e66:: with SMTP id y6mr3106759lfs.184.1643298123642; Thu, 27 Jan 2022 07:42:03 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Shakeel Butt Date: Thu, 27 Jan 2022 07:41:52 -0800 Message-ID: Subject: Re: Backport memcg flush improvements into 5.15 To: Greg KH , Andrew Morton , Linux MM Cc: Ivan Babrou , stable , kernel-team Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 7FBBA40008 X-Stat-Signature: z5x151qy8yzwa8igfeait9uh6d6p6btj Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=mzVnI9hp; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf01.hostedemail.com: domain of shakeelb@google.com designates 209.85.167.51 as permitted sender) smtp.mailfrom=shakeelb@google.com X-Rspam-User: nil X-HE-Tag: 1643298125-246842 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: +Andrew & linux-mm On Thu, Jan 27, 2022 at 7:30 AM Greg KH wrote: > > On Wed, Jan 19, 2022 at 04:15:34PM -0800, Ivan Babrou wrote: > > Hello, > > > > We've seen a significant perf degradation when reading a tmpfs file > > swapped into zram between 5.10 and 5.15. The source of the issue is: > > > > * aa48e47e3906: memcg: infrastructure to flush memcg stats > > > > There's a couple of commits that helps to bridge the gap in 5.16: > > > > * 11192d9c124d: memcg: flush stats only if updated > > * fd25a9e0e23b: memcg: unify memcg stat flushing > > > > Both of these apply cleanly and Shakeel (the author) has okayed the > > backport from his end. He also suggested backporting the following: > > > > * 5b3be698a872: memcg: better bounds on the memcg stats updates > > > > I personally did not test this one, but it applies cleanly, so there's > > probably no harm. I cc'd Shakeel in case you want confirmation on > > that. It's not a part of any tag yet. > > > > Please backport all three (or at least the first two) to 5.15 LTS. > > All now queued up, thanks! Thanks Greg. Adding Andrew (and linux-mm) in CC to let him know the reason for backporting these patches to 5.15 stable tree. > > greg k-h