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-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1ZtAvr-0007Qa-CX for user-mode-linux-devel@lists.sourceforge.net; Mon, 02 Nov 2015 08:57:39 +0000 Received: from ivanoab4.miniserver.com ([78.31.104.92]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES128-SHA:128) (Exim 4.76) id 1ZtAvq-00071y-8l for user-mode-linux-devel@lists.sourceforge.net; Mon, 02 Nov 2015 08:57:39 +0000 Message-ID: <5637257A.8000200@kot-begemot.co.uk> Date: Mon, 02 Nov 2015 08:57:30 +0000 From: Anton Ivanov MIME-Version: 1.0 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> <56372439.2070509@nod.at> In-Reply-To: <56372439.2070509@nod.at> 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: Richard Weinberger , Thomas Meyer Cc: "user-mode-linux-devel@lists.sourceforge.net" On 02/11/15 08:52, Richard Weinberger wrote: > 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. There are quite a few things running so this may indeed be the case. What do you use for userspace (so I can try to reproduce this and debug it)? A. > > 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