From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4972 invoked by alias); 18 Jun 2011 06:22:30 -0000 Received: (qmail 4965 invoked by uid 22791); 18 Jun 2011 06:22:29 -0000 X-SWARE-Spam-Status: No, hits=-6.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 18 Jun 2011 06:22:05 +0000 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p5I6M4JP023186 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sat, 18 Jun 2011 02:22:04 -0400 Received: from localhost (vpn1-4-17.ams2.redhat.com [10.36.4.17]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p5I6M3FP027418; Sat, 18 Jun 2011 02:22:04 -0400 Date: Sat, 18 Jun 2011 06:22:00 -0000 From: "Richard W.M. Jones" To: "Frank Ch. Eigler" Cc: systemtap@sourceware.org Subject: Re: staprun -c deadlocks often Message-ID: <20110618062106.GW803@amd.home.annexia.org> References: <20110617154320.GC18438@amd.home.annexia.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2011-q2/txt/msg00307.txt.bz2 On Fri, Jun 17, 2011 at 02:43:13PM -0400, Frank Ch. Eigler wrote: > rjones wrote: > > [stap command prints the module name, used below] > > staprun -o /tmp/stap -c /bin/ls /home/rjones/.systemtap/cache/44/stap_44fe38ee6f62656645948ce5d275d678_260427.ko > > Just running stap .... -c /bin/ls should give the same results. Or > are you cross-compiling? (If so, there are other methods available > that wouldn't require hand-copying and hand-running staprun.) The reason I'm using staprun is to avoid recompiling the kernel module each time. I'm not sure how necessary this is, since I also noticed that Systemtap seems to cache the module. Will it always avoid recompiling the exact same source? Anyhow, in order to exclude staprun from the equation, I used just stap: sudo \ stap \ -o /tmp/stap \ -c /bin/ls \ -e 'probe module("ext2").statement ("*@*.c:*") { printf ("%s\n", pp()); }' I get basically the same problem, although it appears to be slightly less frequently (1 in 4? 1 in 5?) for some reason. Process listing when it hangs: 29643 pts/5 Ss 0:00 \_ bash 29934 pts/5 S+ 0:00 | \_ sudo stap -o /tmp/stap -c /bin/ls -e probe mo 29935 pts/5 S+ 0:00 | \_ stap -o /tmp/stap -c /bin/ls -e probe mod 29936 pts/5 Sl+ 0:00 | \_ /usr/libexec/systemtap/stapio -o /tmp 29937 pts/5 S+ 0:00 | \_ /usr/libexec/systemtap/stapio -o > > As I say, more often than half the time, instead of printing out a > > directory listing, the staprun command will just hang. [...] > > This sounds like http://sourceware.org/PR10189, where too many warning > messages interfere with non-warning staprun<->module packets. It could be. I'm still getting warning messages (see previous email). Is there a way to get it to discard the warning messages? Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org