From owner-freebsd-current@freebsd.org Sun Jan 21 22:58:03 2018 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 8BDF7EBFFA8 for ; Sun, 21 Jan 2018 22:58:03 +0000 (UTC) (envelope-from johalun0@gmail.com) Received: from mail-wm0-x231.google.com (mail-wm0-x231.google.com [IPv6:2a00:1450:400c:c09::231]) (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 1D14A7FA34; Sun, 21 Jan 2018 22:58:03 +0000 (UTC) (envelope-from johalun0@gmail.com) Received: by mail-wm0-x231.google.com with SMTP id i186so12983829wmi.4; Sun, 21 Jan 2018 14:58:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=t3D0JAnLAY2qwXkfrtzPQtsfTViZXL2ikSmvvaqBoPo=; b=CwvDxPX6yYNliulDR00hBF9CEDY/DrXHYsUZldbMKHEI65stAFtQ7N4UrNPVNmYNuf iI7DkTUdiRVqe6CP2GIw4dsvW6kvcfiTv71PWJeFxPU0ika1ag6g3Hn5SRO0dXzCslKf kdGO6GOncjIfkhhW0n2i3aGLLN7Fcxu885qDxynFcobYRvHSHdz8DO9t8tA+R4AGjgyW Wo7Ny/RBdXvHgpAj55K+J58rYmHV1L1dGm/m7a/ygT7VOiCA2wuN4Dr8t9gx20L5vStS NOaWEw7Ye6cvKvyi7u/SBykb0KRyb0g5NFF0wrLGiDUWBtY8II9H7PrZ993SNv6qkhQN naag== 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=t3D0JAnLAY2qwXkfrtzPQtsfTViZXL2ikSmvvaqBoPo=; b=axSgumSvHs2ni+4WQuOJQMRCDHm6viY02GNrXrMA//5ABWAwpbHJ+rVYeNZO14NVHB ERFzXPBTOm1Y6snhvfvyKx5zey7ahPWj8chRf09raD2K3KX+uDaUHnJA/NT4/Mce4vSw fFyThiDmn9MyUOsvvReL1QKRcfkUO0ptKRoKVMctil6hHC/5kTbqQs+vO83oAgkWPVuv dakM9k0kV0e0tFkgd/MyWMm5EL4dQetW2kYPKjfBUY9EuAe2RkHX3TWVadrHzN/W6jjG ZkX/qpZRTGlC011AaLfir2IZw2Cu4K5boUytOlSyRGQVkxdgBpKeSAe+KndEbxasBW7r kS1Q== X-Gm-Message-State: AKwxytef5waBV61uJRqgivI9sYRgpTIrB/we8thrzizw0tehVXbcvnhE ZGqpv6IfAbuVXHwrmipc92Spok6AHst/b3e1iNU= X-Google-Smtp-Source: AH8x227geMhWzUMxBnXrXrHHrHwa0d+iYwgI63JQhnN0UC4QNFr3QKpyOCm+meIsvotLKrH2CCrpyR1GIo7LTysGVgA= X-Received: by 10.28.179.9 with SMTP id c9mr3204571wmf.99.1516575480479; Sun, 21 Jan 2018 14:58:00 -0800 (PST) MIME-Version: 1.0 Received: by 10.223.136.187 with HTTP; Sun, 21 Jan 2018 14:57:20 -0800 (PST) In-Reply-To: <1516569725.42536.99.camel@freebsd.org> References: <64218617-98d2-0e6e-5872-e44106e61bf7@selasky.org> <1516569725.42536.99.camel@freebsd.org> From: Johannes Lundberg Date: Sun, 21 Jan 2018 22:57:20 +0000 Message-ID: Subject: Re: Periodical interrupt storm when playing game with USB keyboard To: Ian Lepore Cc: Hans Petter Selasky , freebsd-current Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Jan 2018 22:58:03 -0000 On Sun, Jan 21, 2018 at 9:22 PM, Ian Lepore wrote: > On Sun, 2018-01-21 at 22:07 +0100, Hans Petter Selasky wrote: > > On 01/21/18 21:45, Johannes Lundberg wrote: > > > > > > What does kern.eventtimer.periodic do? The sysctl description > > > wasn't > > > that elaborate... > > It turns off re-programming the timer every time there is a new > > callout > > with earlier completion time. > > > > --HPS > > Well, it does more than that. It makes the system run "the old way" > where there are periodic timer interrupts that happen whether they need > to or not (bad for power saving), and there's no way to schedule > anything to happen on intervals other than when the periodic ticks > occur (so if kern.hz = 1000 and you ask to sleep for a microsecond you > may actually sleep up to a millisecond). > > Thanks for the further explanation. I curious as to where the problem might be though.. It is the game's binary-only Linux executable (Unreal Engine 2.5), Linux SDL 1.2, or on the FreeBSD side? Haven't experienced anything similar with Quake3... Switching to periodic timer feels like overkill but it does the job as a work around. > -- Ian >