From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f53.google.com (mail-oi0-f53.google.com [209.85.218.53]) by kanga.kvack.org (Postfix) with ESMTP id DB8E36B0032 for ; Fri, 27 Mar 2015 00:49:55 -0400 (EDT) Received: by oicf142 with SMTP id f142so58084755oic.3 for ; Thu, 26 Mar 2015 21:49:55 -0700 (PDT) Received: from mail-ob0-f180.google.com (mail-ob0-f180.google.com. [209.85.214.180]) by mx.google.com with ESMTPS id r129si513899oia.126.2015.03.26.21.49.55 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 26 Mar 2015 21:49:55 -0700 (PDT) Received: by obcjt1 with SMTP id jt1so63121934obc.2 for ; Thu, 26 Mar 2015 21:49:54 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20150326131822.fce6609efdd85b89ceb3f61c@linux-foundation.org> References: <359c926bc85cdf79650e39f2344c2083002545bb.1427347966.git.viresh.kumar@linaro.org> <20150326131822.fce6609efdd85b89ceb3f61c@linux-foundation.org> Date: Fri, 27 Mar 2015 10:19:54 +0530 Message-ID: Subject: Re: [RFC] vmstat: Avoid waking up idle-cpu to service shepherd work From: Viresh Kumar Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: hannes@cmpxchg.org, Christoph Lameter , Linaro Kernel Mailman List , Linux Kernel Mailing List , vinmenon@codeaurora.org, shashim@codeaurora.org, Michal Hocko , mgorman@suse.de, dave@stgolabs.net, koct9i@gmail.com, Linux Memory Management List , Suresh Siddha , Peter Zijlstra , Thomas Gleixner On 27 March 2015 at 01:48, Andrew Morton wrote: > Shouldn't this be viewed as a shortcoming of the core timer code? Yeah, it is. Some (not so pretty) solutions were tried earlier to fix that, but they are rejected for obviously reasons [1]. > vmstat_shepherd() is merely rescheduling itself with > schedule_delayed_work(). That's a dead bog simple operation and if > it's producing suboptimal behaviour then we shouldn't be fixing it with > elaborate workarounds in the caller? I understand that, and that's why I sent it as an RFC to get the discussion started. Does anyone else have got another (acceptable) idea to get this resolved ? -- viresh [1] http://lists.linaro.org/pipermail/linaro-kernel/2013-November/008866.html -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org