X-Recipient: archive-cygwin AT delorie DOT com
DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:mime-version:in-reply-to:references:from:date
	:message-id:subject:to:content-type; q=dns; s=default; b=OU0xVXk
	d3/RCSk948f4v0dCstTM8lvEovASnwAqROowAPBiXu6IIFQQ7dVxPIVOPtZ7Ex6L
	AeyKx/FdtJbEaaNG//6wrU2ywj3KsvFbMfOq4KTg4fathKAeKbcI5lSRG/LyWueX
	JwObB3gQdtl207PcnDOFG2pjV1dz82cuhJR0=
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:mime-version:in-reply-to:references:from:date
	:message-id:subject:to:content-type; s=default; bh=9OYFYJ8OKdgUa
	rs1w0tmDJNGRKI=; b=svHyH9BRTocok8MCdCbJSR1W0pLBDEYdEqHFRgGiNHeQN
	+IHpLsX+kCTbLlOsJD5e9qogfAih5Av0CxP5w91emzc5h1nlDAh00ykgAnKunjQc
	Lxg957s0IpYZwPh8p/6+3p40ZyWiJGexQXLyWHIMjGlfzl6XZQe3DXi1cLFoYg=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com
Authentication-Results: sourceware.org; auth=none
X-Virus-Found: No
X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy=D*nexgo.de, spin, stays, watched
X-HELO: mail-pl0-f46.google.com
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;        d=1e100.net; s=20161025;        h=x-gm-message-state:mime-version:sender:in-reply-to:references:from         :date:message-id:subject:to;        bh=yNrfWLaSwrVt6X+fjYseem71c0FKSlp2M0AWp6SL8jc=;        b=kHA7AsZWsQx23OF9jOnwnE19ZkZh072k8AExq9OVcwxUizByGVQsvLhbhDeqAQFjQd         /0PYkzD+0MhUY0UB/XwsEour5uUzYc5mnbyXG3uePRPwjv1O45OdjHJU3k0IITHekYzJ         UdXXauBchESYB3H/i8+Dv69i9Q3fyZmKq9S+nRQ6qLEIgA3L+KaGzPNrTBZaRmDpEVyU         +EvnfNuzvUtwr7XtL+91HLS92HlmORPoE81eWg4hJDhwL+3AcVeezwfmMhHr97J6qwQL         Y+dupZ3mlNwbFrQJG7ctI36rEv9F22MJA24GVkCoW3ex2kz0th33mUad8MaVbx0XEat6         e4Fw==
X-Gm-Message-State: AElRT7EyYPJqf+6zsKJwwwNwQ7iXsNd2G4S/LiOexnbNPiIzWxkdRV3c	9e1hCnTyZS2THO0o+4Hnkz3pYEJJ/w34hLeRJIY=
X-Google-Smtp-Source: AG47ELu2aKfGIpY72x10zZKlAYQ5CufUIiV0Zyh5D4Dk3kBts7S4qWWMqegSvZ6Zd6rToHYJPBD46oCuMpZcPKyZKls=
X-Received: by 2002:a17:902:8602:: with SMTP id f2-v6mr22138519plo.6.1521670048812; Wed, 21 Mar 2018 15:07:28 -0700 (PDT)
MIME-Version: 1.0
In-Reply-To: <877eq5fedf.fsf@Rainer.invalid>
References: <CAPF-yOYzTr-jh__S_imaAcdk5Vf4tGD1xFLuTDu4-qsg_+HiCA AT mail DOT gmail DOT com> <877eq5fedf DOT fsf AT Rainer DOT invalid>
From: Dan Kegel <dank AT kegel DOT com>
Date: Wed, 21 Mar 2018 15:07:28 -0700
Message-ID: <CAPF-yOb8O+Xhp3yi9wGFFJDvrSA0W24LZ+1adAcga--H7=qaZw@mail.gmail.com>
Subject: Re: Odd hang in python waiting for child; strace wakes hung process?
To: cygwin AT cygwin DOT com
Content-Type: text/plain; charset="UTF-8"
X-IsSubscribed: yes

On Wed, Mar 21, 2018 at 11:54 AM, Achim Gratz <Stromeko AT nexgo DOT de> wrote:
> Well, with the sporadic hanging/defunct processes at work my routine is
> to send CONT to all Cygwin processes, then HUP/KILL to anything that's
> still not live or gone and then another round of CONT.  This works
> _most_ of the time, anything more stubborn I /bin/kill -f usually.

Since I wrote, both bots hung again.  This time I verified:
0) both had the defunct git process as expected
1) kill -CONT the-pid doesn't do anything, nor does kill -9.  It's truly wedged.
2) the process stays in its spin hang until you ^C strace -p the-pid
3) ^C-ing the strace causes the process to terminate (strace alone doesn't)
4) taskkill /pid the-task /f also kills the process successfully.

So I could write a script that watched for defunct git processes
and taskkilled their parent.  Build jobs would fail, but at least
the bot would stay up.  Of course it would be much nicer if
the cygwin python process didn't get wedged.

Alternately, I suppose I could try running native python...
or cygwin's python3... but dangit, kill -9 should work.
- Dan

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple