Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com X-Authentication-Warning: slinky.cs.nyu.edu: pechtcha owned process doing -bs Date: Tue, 24 Sep 2002 09:49:48 -0400 (EDT) From: Igor Pechtchanski Reply-To: cygwin@cygwin.com To: Anthony Heading cc: cygwin@cygwin.com, Subject: Re: 2.5.5-1 rsync hangs In-Reply-To: <20020924102940.GA25046@tkd-fires-02.ja.jpmorgan.com> Message-ID: Importance: Normal MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII On Tue, 24 Sep 2002, Anthony Heading wrote: > On Mon, Sep 23, 2002 at 01:06:22PM -0700, Sudheer Tumuluru wrote: > > > > I am having the same problem with rsync 2.5.5-1. I am > > trying to rsync a couple of short text files between a linux server and > > Win2k Professional boxes with cygwin. About 20% of the time, rsync freezes > > at the end of the transfer, and I can't kill the rsync process in > > cygwin even if I give it a 9 (SIGTERM) signal. This happens mostly on dual-processor > > machines but it did happen once on the single proc machine as well. > > Me too. I spent this afternoon debugging. There doesn't appear to be > anything wrong with rsync - looks rather more like something in cygwin > signal delivery is ill. > > In my case I'm trying to pull files onto Windows(XP) from Unix(Solaris). > > rsync forks in this case; the parent process generates the filelisT > while a child process does the receiving. (Something like that, at > least; I guess it's for deadlock avoidance) > > At the end, the parent process waves farewell to the remote server, > and then does a kill(..., SIGUSR2) on the child pid to tell it to exit. > > This signal seems to get lost, as suggested above, some moderate > percentage of the time. > > The child process is supposedly waiting for this signal inside > msleep(), which calls select() to wait in 20ms bursts. In the > cases that the child manages to reach the select() in time to > start waiting, I didn't observer any hangs. But consistently > if the kill was received before that point, the child process > simply locks up. > > This suggests that hack workaround of adding a call to > say msleep(30) just before the line kill(pid, SIGUSR2) in > main.c:do_recv(). > > With that kludge in, I haven't seen any hangs in a few hundred > trials. YMMV, but it might be a helpful bandaid until some > cygwin expert has the chance fix things properly. > > Rgds > > Anthony Hmm, how about a patch? Igor -- http://cs.nyu.edu/~pechtcha/ |\ _,,,---,,_ pechtcha@cs.nyu.edu ZZZzz /,`.-'`' -. ;-;;,_ igor@watson.ibm.com |,4- ) )-,_. ,\ ( `'-' Igor Pechtchanski '---''(_/--' `-'\_) fL a.k.a JaguaR-R-R-r-r-r-.-.-. Meow! "Water molecules expand as they grow warmer" (C) Popular Science, Oct'02, p.51 -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/