From owner-freebsd-hackers@freebsd.org Mon Aug 20 16:24:00 2018 Return-Path: Delivered-To: freebsd-hackers@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 52D90107470A for ; Mon, 20 Aug 2018 16:24:00 +0000 (UTC) (envelope-from danilogondolfo@gmail.com) Received: from mail-vk0-f66.google.com (mail-vk0-f66.google.com [209.85.213.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id EF6CF75492 for ; Mon, 20 Aug 2018 16:23:59 +0000 (UTC) (envelope-from danilogondolfo@gmail.com) Received: by mail-vk0-f66.google.com with SMTP id w193-v6so3016987vke.2 for ; Mon, 20 Aug 2018 09:23:59 -0700 (PDT) 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=CslWmNn6B016rJLi+3/ZkdkIHSHCF4kezSGNIKJFW4g=; b=Fp9FFLtjuCz/x71VFKTaf5eS9uG4zZt/vP0fmKX054mFDsGaU4xyd5WyQPJw+ZdCeC agY0z0SyZ2B+/6VZ4fm9jpQEaDFs00ufdi6+z9WXH5FcB/dTCjbOFXJ3jLv4QyX9XJYO +GSlkUI6+x98R7tBnHU7M91DVFUO8OwzsXsFerJXTSKMwvyoAQoFUZ84G/n/juvUw3Nm KNNc09/yjSUbfnm85FdjHDdo9hllmQVUyXVJhNFCphZwGqCv5rhUz3yDjR2piI9Bu6A5 k0rRGnWR7JVzIXyWtGw0fKCfWUs1/v31DBfVeMLxJ1/xjfsfhMeC9vamExKj3RnimPbp SNiw== X-Gm-Message-State: APzg51A7PVjdYOCe3N3P00BDGSW3NGBwPjtefdvu7413P5+FUBDhJFKl J9sJ15fhQnW3qDzPNcbBsPmvii02Z/pVNT5JRj7Ex2N7 X-Google-Smtp-Source: ANB0VdbDRPxEylsgmHRV8yznRwDh1pAGl9q/mh/TE5R/OC0tc+T7FeI3mkKgjOBurTaW0yqfGQQYYXbCpayV+pEZ9E4= X-Received: by 2002:a1f:41ce:: with SMTP id o197-v6mr1514344vka.63.1534778915630; Mon, 20 Aug 2018 08:28:35 -0700 (PDT) MIME-Version: 1.0 References: <95C34771-8D0B-489A-88DA-09AF0D244A1C@yahoo.com> In-Reply-To: <95C34771-8D0B-489A-88DA-09AF0D244A1C@yahoo.com> From: =?UTF-8?Q?Danilo_Eg=C3=AAa_Gondolfo?= Date: Mon, 20 Aug 2018 12:29:24 -0300 Message-ID: Subject: Re: rand_harvestq high cpu usage when /dev/urandom is used To: marklmi@yahoo.com Cc: aliovx@gmail.com, freebsd-hackers@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.27 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 Aug 2018 16:24:00 -0000 On Mon, Aug 20, 2018 at 8:54 AM Mark Millard via freebsd-hackers < freebsd-hackers@freebsd.org> wrote: > > > On 2018-Aug-20, at 4:27 AM, Ali Abdallah wrote: > > > . . . > > Also, I read on > > > https://lists.freebsd.org/pipermail/freebsd-current/2013-November/046683.html > > someone saying that sysctls to turn off harvesting is documented in > > random(6) > > > It says random(4), so: > > < > https://www.freebsd.org/cgi/man.cgi?query=random&sektion=4&manpath=freebsd-release-ports > >. > > > . . . > > === > Mark Millard > marklmi at yahoo.com > ( dsl-only.net went > away in early 2018-Mar) > > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" > I can confirm this is happening. It's easily reproducible: dd if=/dev/urandom of=/dev/null rand_harvestq eat 100% of one CPU for minutes, in my case the system became unresponsive (at least the graphical interface, it freezes for few seconds). I'm running FreeBSD 12.0-ALPHA2 #14 r337973M (sorry if I sent it twice)