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 X-Spam-Level: X-Spam-Status: No, score=-5.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_2 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6135FC433E2 for ; Sat, 12 Sep 2020 20:59:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0ABF0207FB for ; Sat, 12 Sep 2020 20:59:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=hansenpartnership.com header.i=@hansenpartnership.com header.b="Xaqe/rNq"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=hansenpartnership.com header.i=@hansenpartnership.com header.b="Xaqe/rNq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725897AbgILU74 (ORCPT ); Sat, 12 Sep 2020 16:59:56 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:57722 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725891AbgILU7z (ORCPT ); Sat, 12 Sep 2020 16:59:55 -0400 Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 79E8A8EE0E2; Sat, 12 Sep 2020 13:59:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1599944393; bh=7hEQKjI9O8nacR0TWKtYnXQr5cvLv5P4viB2BZaAnck=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=Xaqe/rNqGsZqGTYX7F7OsxrQprW1LzXd9FJTjf/UcehK1yt9jLTqhef+GliZhR8Fr aY4xZ1S10JW6/XWKoklAfSd3JN1USn47F4uuRiGIOWZdUvovqt6ZvjpYb81FkJYruE l9m+fhEVU4HL7CFu0JUjRyBBZltXPubDNgtxLcgM= Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gxACGVMy-c8L; Sat, 12 Sep 2020 13:59:53 -0700 (PDT) Received: from [153.66.254.174] (c-73-35-198-56.hsd1.wa.comcast.net [73.35.198.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id 87CFF8EE07B; Sat, 12 Sep 2020 13:59:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1599944393; bh=7hEQKjI9O8nacR0TWKtYnXQr5cvLv5P4viB2BZaAnck=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=Xaqe/rNqGsZqGTYX7F7OsxrQprW1LzXd9FJTjf/UcehK1yt9jLTqhef+GliZhR8Fr aY4xZ1S10JW6/XWKoklAfSd3JN1USn47F4uuRiGIOWZdUvovqt6ZvjpYb81FkJYruE l9m+fhEVU4HL7CFu0JUjRyBBZltXPubDNgtxLcgM= Message-ID: <1599944388.6060.25.camel@HansenPartnership.com> Subject: Re: Kernel Benchmarking From: James Bottomley To: Linus Torvalds , Amir Goldstein , Hugh Dickins Cc: Michael Larabel , Ted Ts'o , Andreas Dilger , Ext4 Developers List , Jan Kara , linux-fsdevel Date: Sat, 12 Sep 2020 13:59:48 -0700 In-Reply-To: References: <6e1d8740-2594-c58b-ff02-a04df453d53c@MichaelLarabel.com> <8bb582d2-2841-94eb-8862-91d1225d5ebc@MichaelLarabel.com> <0cbc959e-1b8d-8d7e-1dc6-672cf5b3899a@MichaelLarabel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Sat, 2020-09-12 at 10:59 -0700, Linus Torvalds wrote: [...] > Any other suggestions than those (a)-(d) ones above? What about revert and try to fix the outliers? Say by having a timer set when a process gets put to sleep waiting on the page lock. If the time fires it gets woken up and put at the head of the queue. I suppose it would also be useful to know if this had happened, so if the timer has to be reset because the process again fails to win and gets put to sleep it should perhaps be woken after a shorter interval or perhaps it should spin before sleeping. I'm not advocating this as the long term solution, but it could be the stopgap while people work on (c). James