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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 419B8C433E0 for ; Thu, 11 Jun 2020 01:40:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F22912072F for ; Thu, 11 Jun 2020 01:40:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="KOgY4dn1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726361AbgFKBkj (ORCPT ); Wed, 10 Jun 2020 21:40:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726163AbgFKBkj (ORCPT ); Wed, 10 Jun 2020 21:40:39 -0400 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F4CEC08C5C1 for ; Wed, 10 Jun 2020 18:40:39 -0700 (PDT) Received: by mail-pf1-x444.google.com with SMTP id z63so1012294pfb.1 for ; Wed, 10 Jun 2020 18:40:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=rAVjwDE1YQNexj2tuztG00TSNSIMXta4Z0XlVbeaKyY=; b=KOgY4dn1RDtFEv5le+jydJNJJs4GpT4KM2L7flHPEDh2kV5gIFbN4xce5zD+IWzv1n BoSCLX6LwVeSt7ybLNPpHp4OqFQVWv9gLlXqbdW45LDdA9b9jbQarTjMgGjA0eEuipxT zGuy1+P6KjoF7+71MYVnrqm8meqQ/2icv7SkzanQq1rgsAgdLZKvl+fVIhPqM8crWzk/ 7QjiJ5wdADoWNx/g1dAIckE3igW/l2P9gfHCKNCTbF0ffPrOdEjsrBSfIjBEqtn92hqs /moN5dGMWGzPuCw3qRs+M7eBvWUXYouaqdBTYuj4InxLNw91cDg639acJ+Ow5RlJmyRd hKwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=rAVjwDE1YQNexj2tuztG00TSNSIMXta4Z0XlVbeaKyY=; b=VtC+5q4wLS0Pu+Gbxq72k945xoDppy6wlObQmZE1kDDPWi9rY1aQfMAGAY51X/pcP/ XnjU+oUpmzrBNmZyB/bxmfX/t+QW/fi7Ra+YDgWzO+rg7yE3Ec32XV8xQXXCiY6Oo8rv T3n1Y5L1n2FOaSx+PzHPoZribXuMh5TyUowgxWYyUDdKgyWxIi8uRmo63EjrN9aEezzj cS7/rq3gStvHzJgBwfJDMpJ29HMBmdxqFfSBjAolKhF7YxjVua0dRaM9MZe/G6mHScCb 4D+I3U43mZ16vNwPnM/699nT8fbB1COrkBPU3GbseCxqC1RSHU19ZXHPHVrho6BzRXa2 N3QA== X-Gm-Message-State: AOAM531/bm0Ko6PqXfR/QH8bO/1m3GtRE6NpSUifVtp9fELOVb5eBoBQ E96Qd5XVibeofo8+e1l8ld0ec/Z2GSK+Sg== X-Google-Smtp-Source: ABdhPJxrfG7dA4djhvtWiGPLR80xL8TuOz4qfjRqrQK3rHBjbuRi8QeR14OuHsnycW9+Okanm3wpfw== X-Received: by 2002:aa7:82cb:: with SMTP id f11mr5188700pfn.81.1591839638568; Wed, 10 Jun 2020 18:40:38 -0700 (PDT) Received: from [192.168.1.188] ([66.219.217.173]) by smtp.gmail.com with ESMTPSA id q65sm1173385pfc.155.2020.06.10.18.40.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 10 Jun 2020 18:40:38 -0700 (PDT) Subject: Re: [PATCH] io_uring: add EPOLLEXCLUSIVE flag to aoid thundering herd type behavior To: Jiufei Xue , io-uring@vger.kernel.org Cc: joseph.qi@linux.alibaba.com References: <1591769708-55768-1-git-send-email-jiufei.xue@linux.alibaba.com> <84caca8b-1e34-cc70-c395-c826b7415f35@linux.alibaba.com> From: Jens Axboe Message-ID: <6666d2d5-e85e-57e0-b6a9-077ab20f2340@kernel.dk> Date: Wed, 10 Jun 2020 19:40:36 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <84caca8b-1e34-cc70-c395-c826b7415f35@linux.alibaba.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 6/10/20 7:36 PM, Jiufei Xue wrote: > > > On 2020/6/11 上午8:01, Jens Axboe wrote: >> On 6/10/20 12:15 AM, Jiufei Xue wrote: >>> Applications can use this flag to avoid accept thundering herd. >> >> So with this, any IORING_OP_POLL_ADD will be exclusive. Seems to me >> that the other poll path we have could use it too by default, and >> at that point, we could clean this up (and improve) it further by >> including that? >> > Sorry, I have sent the wrong patch. I think the flag should be determined by > user, I will send the new version soon. That's sort of what I assumed as well. -- Jens Axboe