From owner-svn-src-all@freebsd.org Fri Apr 13 17:31:14 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B6420F9913B for ; Fri, 13 Apr 2018 17:31:14 +0000 (UTC) (envelope-from shurd@llnw.com) Received: from mail-lf0-x234.google.com (mail-lf0-x234.google.com [IPv6:2a00:1450:4010:c07::234]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 1A87E77A62 for ; Fri, 13 Apr 2018 17:31:14 +0000 (UTC) (envelope-from shurd@llnw.com) Received: by mail-lf0-x234.google.com with SMTP id m14-v6so1665000lfc.0 for ; Fri, 13 Apr 2018 10:31:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=llnw.com; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=75yGyqpLDd5ulEq7wTi62uV6uOCZ4Vdj8lRwptVnnQ8=; b=FrLUdvZXCNfwok1hXtltXPI29IMNdt38AUmI6XMmLrVcyT0+S64xMg79r/m0DqOzlU E+ANZb2p29jwW2Dxi/9QuIxEDl2mADioHSNZCoBGU8s1bqNzJmLlrehBxmc7A5hgzeHZ mQh0CRzIYxzLVmi4GEfXWHsrSYeZF+onFhuHtXT7JCkvaJrXp37uWtz+pVgDniqqDtV5 ENC4ujSpQn9iTAvT/EnkDdvMV4vNoUaj3tbhyY66prqjFen8SERDc5XGBz/GweECDt/2 1E0jKu91UB4QENV+QbEPegsVbhZNXGqrxjFdzh9DppfSiijUUtEPBWoVYzcOzgaJfrEm YjPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=75yGyqpLDd5ulEq7wTi62uV6uOCZ4Vdj8lRwptVnnQ8=; b=AOXnwb7vmj75iBibdEjZwUO9I2gICeUhJ3WnHXoKNwyi8pV9/uZ08Sxwzqv/O/+y9o H3CjqbYfg8MR5/QoCjsas+wNNI8vE8GjrE68UFLTxbTMZhxDTs1DoaU5wTcALAjMqggH dCpmWWBNcxLBjG9xMxP/I16xUcezOxWmpor/t0BBK6Tw6wZC2UIja6P+09fzrMVcENjH IvASKhdPmfY8eX9ShrPAyi3ZBrca34n2ow0424cVkEOi7NnS/ZukfHh/RGhRssAGq8Nf nLs5MUbTZzeGYJqcPqyBvgRpysE9DyoWhoXQ9V7P0IfPos4VOyhjixpQKjdDPi27ap3G ddGg== X-Gm-Message-State: ALQs6tDhp7P6OAdCcGT4FD/dznZgN5OLV4XduAySoPH34fxrPCZx3oTw 4RPj1Zbq0ngVfvHofRNS4Pz4ncODzRw24/fqG0mg5w== X-Google-Smtp-Source: AIpwx4+luufNHF9BKEKkO9AjiDo2Pu/sJUo/xvWyXpCf5td9V08OywhckyKxqrLHNtV+owWlqixYX9h6j3xQ4z7ITx4= X-Received: by 2002:a19:a60a:: with SMTP id p10-v6mr9139646lfe.41.1523640671913; Fri, 13 Apr 2018 10:31:11 -0700 (PDT) MIME-Version: 1.0 Received: by 10.46.134.140 with HTTP; Fri, 13 Apr 2018 10:31:11 -0700 (PDT) In-Reply-To: References: <201804121906.w3CJ6FZo092138@repo.freebsd.org> From: Stephen Hurd Date: Fri, 13 Apr 2018 13:31:11 -0400 Message-ID: Subject: Re: svn commit: r332447 - stable/11/sys/dev/ixgbe To: Ryan Stone Cc: Stephen Hurd , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Apr 2018 17:31:15 -0000 Yeah, I'm looking at the changes that caused this now. Hopefully I'll have this updated today. On Thu, Apr 12, 2018 at 4:01 PM, Ryan Stone wrote: > Spinning in the kernel for a full second is a really bad idea. At > minimum this is going to hold off all callouts from one of the callout > threads for up to a full second as ixgbe_local_timer() waits for the > core mutex. That chews up two CPU cores doing busy-wait loops (the > ixgbe_stop() thread busy-waits in msec_delay and the callout thread > adaptively spins waiting for the mutex). If any other thread tries to > acquire the core lock they also adaptively spin on the mutex chewing > up yet more cores. This includes any threads trying to fetch > interface status (e.g. ifconfig), various interrupt handlers, etc. > -- [image: Limelight Networks] Stephen Hurd* Principal Engineer* EXPERIENCE FIRST. +1 616 848 0643 <+1+616+848+0643> www.limelight.com [image: Facebook] [image: LinkedIn] [image: Twitter]