From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1ZtAqh-0003tR-Fw for user-mode-linux-devel@lists.sourceforge.net; Mon, 02 Nov 2015 08:52:19 +0000 Received: from a.ns.miles-group.at ([95.130.255.143] helo=radon.swed.at) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1ZtAqg-0006t4-6v for user-mode-linux-devel@lists.sourceforge.net; Mon, 02 Nov 2015 08:52:19 +0000 References: <1445416947-824802-1-git-send-email-aivanov@brocade.com> <562D236E.7020108@kot-begemot.co.uk> <562DFC90.9030308@nod.at> <5631BB4E.4010301@kot-begemot.co.uk> <1446304232.3238.8.camel@m3y3r.de> <5634DAA4.70308@nod.at> <1446304594.3238.11.camel@m3y3r.de> <5634DC7B.3010707@nod.at> <56371B6D.3080506@kot-begemot.co.uk> <563720BA.20107@nod.at> <563721BB.10003@kot-begemot.co.uk> From: Richard Weinberger Message-ID: <56372439.2070509@nod.at> Date: Mon, 2 Nov 2015 09:52:09 +0100 MIME-Version: 1.0 In-Reply-To: <563721BB.10003@kot-begemot.co.uk> List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net Subject: Re: [uml-devel] [PATCH v3] um: Switch clocksource to hrtimers To: Anton Ivanov , Thomas Meyer Cc: "user-mode-linux-devel@lists.sourceforge.net" Am 02.11.2015 um 09:41 schrieb Anton Ivanov: > On 02/11/15 08:37, Richard Weinberger wrote: >> Hi! >> >> Am 02.11.2015 um 09:14 schrieb Anton Ivanov: >>> I was testing under similar conditions (CPU pinning using taskset -c 0 on a multicore). >>> >>> I have removed it and run some retests - I cannot reproduce the hang at this point with my config >>> >>> I am going to run a defconfig and compare the results to see if this will give me any insights on the root cause. >> I can reproduce on both my build machine (8 core) and my laptop (4 core). >> If it helps I can share the rootfs. >> >> On my laptop I was able to reproduce within 5 minutes. >> 1. make defconfig ARCH=um >> 2. make -j 4 linux ARCH=um >> 3. ./linux ubda=../Downloads/Debian-Squeeze-AMD64-root_fs mem=1G >> 4. login to tty0 >> 5. wait a few minutes >> 6. try to run top, it will hang in nanosleep > > Pretty much the same. Does not hang, multiple test runs. Userspace is a relatively full install of a debian jessie. > > I ran deconfig and did a diff. The prime suspect differences between my config and defconfig are stack order 3 (not 1) and io sched of cfq, not deadline. > > I am going to retest just with these first to see if one of them is the culprit, if that does not make a difference, run it with defconfig and try to reproduce the hang. I'm pretty sure that you don't see the issue as your Jessy userspace uses nanosleep periodically. Thanks, //richard ------------------------------------------------------------------------------ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel