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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 CAACCCA9ECF for ; Fri, 1 Nov 2019 22:12:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D68C21897 for ; Fri, 1 Nov 2019 22:12:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572646377; bh=R3zHF33lXpbXV7nnsIRwzSf5C2VJ9cDXB6diPjhN9b0=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=Ch6dE+nc8yMgbytezpO588YiblLJHdWTAIZUvDCQO6N7M82V+iudg2WhRpJBqmskk JBKcARPl8x+qiNgBdgxE73wQrREdjRl85S4Pt+/SmxqUVETu5WJLtOm5z1deZxOk7M 5BPr5y5j6RPLLAoRo7bc8DOLox6VI9M50jyqrYUc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728137AbfKAWMx (ORCPT ); Fri, 1 Nov 2019 18:12:53 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:37105 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727270AbfKAWMo (ORCPT ); Fri, 1 Nov 2019 18:12:44 -0400 Received: by mail-lj1-f194.google.com with SMTP id v2so11695179lji.4 for ; Fri, 01 Nov 2019 15:12:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=sgYt+P3xDWHpqkCDVDLjgLKgMrsRwGebg6HQkCjAc5w=; b=O3mYYvlU9vmiWCuVM7D5zeynWjET9sBTNe2UP3ZA3GeXbBriHFMqoPk2kJgyTgcAeI BstBtBLU16kkJaWSMcP9+57VaYHHgUIqojJCqULremk/l27m2Dlyko2Sd9hhC3Y74UKd ZPG4og+yRVtEHOd/O+5D/qMCxYtxUKUSxHi24= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=sgYt+P3xDWHpqkCDVDLjgLKgMrsRwGebg6HQkCjAc5w=; b=Sv9oyyuzAx7w6913aignzqCcGf3oHw/mfn8TdxkBeId/Wxsd/iyl+ojHCpXVnZBkby JJkFMl9CWwe/KVMsKMHPxkPNx7PyOQGTZVRnNeLtc5glec0Nqisml6QnC8QyOv7minCW pEwvoRaZdu0zbz2T1IcH568Su8ejAlNrMpNpX9g0YK5Q4UZkAarqy7LvdVUGVzWP8zJj qN9X2jrXqXb/hwPHkXFpfRhMhNECio3C+153umgKZDyaI8v36XMf9MiJP4M473ykGDXn lQIAZA6jMn1EEaLoROeQ5Ac6UqUHd5pWbYTjTrDZvATr1X/QnTcrfETWFpgb9xJSDPiK 4DXg== X-Gm-Message-State: APjAAAWtmCoDvbd0+XFEYybeQEJg7/ltnANkpPAkauheYSst4ewPB3AN /qGMT5JwhBTf4ETDEymXzwhfVLSHPFY= X-Google-Smtp-Source: APXvYqydAU1WxGb4r86WMgLzrL9qRdd2aoUBeSLJzmgTLBh5RlTh+a2l06igJQihe7HzzJSus++Qvg== X-Received: by 2002:a2e:6817:: with SMTP id c23mr9541624lja.91.1572646362695; Fri, 01 Nov 2019 15:12:42 -0700 (PDT) Received: from mail-lf1-f45.google.com (mail-lf1-f45.google.com. [209.85.167.45]) by smtp.gmail.com with ESMTPSA id t4sm2771024lji.40.2019.11.01.15.12.40 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 01 Nov 2019 15:12:40 -0700 (PDT) Received: by mail-lf1-f45.google.com with SMTP id b20so8256771lfp.4 for ; Fri, 01 Nov 2019 15:12:40 -0700 (PDT) X-Received: by 2002:a19:6f0e:: with SMTP id k14mr8678681lfc.79.1572646359613; Fri, 01 Nov 2019 15:12:39 -0700 (PDT) MIME-Version: 1.0 References: <157262963995.13142.5568934007158044624.stgit@warthog.procyon.org.uk> <13964.1572645926@warthog.procyon.org.uk> In-Reply-To: <13964.1572645926@warthog.procyon.org.uk> From: Linus Torvalds Date: Fri, 1 Nov 2019 15:12:23 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFC PATCH 00/11] pipe: Notification queue preparation [ver #3] To: David Howells Cc: Rasmus Villemoes , Greg Kroah-Hartman , Peter Zijlstra , Nicolas Dichtel , raven@themaw.net, Christian Brauner , keyrings@vger.kernel.org, linux-usb@vger.kernel.org, linux-block , LSM List , linux-fsdevel , Linux API , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Nov 1, 2019 at 3:05 PM David Howells wrote: > > Changing those to non-sync: Your benchmark seems very insensitive to just about any changes. I suspect it is because you only test throughput. Latency is what the pipe wakeup has been optimized for, and which tends to be much more sensitive to other changes too (eg locking). That said, I'm not convinced a latency test would show much either. Linus