Re: [Libguestfs] [ovirt-devel] virt-v2v become zombie via python cpopen on error

On Wed, Mar 30, 2016 at 3:32 PM, Shahar Havivi <shaharh(a)redhat.com&gt; wrote: > On 30.03.16 14:28, Nir Soffer wrote: >> On Wed, Mar 30, 2016 at 1:36 PM, Michal Skrivanek >> <michal.skrivanek(a)redhat.com&gt; wrote: >> > >> >> On 30 Mar 2016, at 11:49, Richard W.M. Jones <rjones(a)redhat.com&gt; wrote: >> >> >> >> On Wed, Mar 30, 2016 at 12:19:35PM +0300, Shahar Havivi wrote: >> >>> Hi, >> >>> >> >>> We encounter a problem in VDSM project that virt-v2v become zombie task while >> >>> importing vm from vmware. >> >>> When virt-v2v is in 'copy disk' mode and we someone deletes the vm at vmware >> >>> the process hang in read() method, >> >>> I am pretty sure that its not virt-v2v problem because when I run it from the >> >>> shell virt-v2v exit with an error, still maybe someone have an idea.... >> >>> >> >>> I wrote a small python script that encounter the problem: >> >>> >> >>> ---------------------------------------------------------------------------- >> >>> from cpopen import CPopen >> >>> >> >>> env = {'LIBGUESTFS_BACKEND': 'direct'} >> >>> cmd = ['/usr/bin/virt-v2v', '-ic', >> >>> 'vpx://....', '-o', >> >>> 'local', '-os', '/tmp', '-of', 'raw', '-oa', 'sparse', >> >>> '--password-file', '/tmp/passwd', '--machine-readable', 'bbb'] >> >>> p = CPopen(cmd, env=env) >> >>> while p.returncode is None: >> >> p.returncode just return the instance variable, there is no wait() involved. >> >> The right way: >> >> while p.poll() is None: > the problem is proc.stdout.read(1) didn't raise and error when the stream > closed but return ''. > its a CPopen behaviour and works differently in subprocess. No, it works the same in both, this was just a bug in our code. Fixed in https://gerrit.ovirt.org/55477 > >> ... >> >> p.returncode calling wait is non-standard feature in vdsm AsyncProc >> wrapper. This is >> the object used by v2v vdsm module, so there accessing p.returncode does call >> p.poll(). >> >> These non-standard apis will be removed from vdsm, please do not use them. >> >> >>> c = p.stdout.read(1) >> >>> print c >> >>> ---------------------------------------------------------------------------- >> >> >> >> An actual zombie task? That would indicate that the parent process >> >> (your Python program) wasn't doing a wait system call. >> >> >> >> I downloaded the cpopen-1.4 program, and it doesn't appear to call any >> >> of the wait*(2) system calls anywhere, so that could be the problem. >> > >> > I suppose the cpopen parameters are not alright…I’m sure vdsm developers can help with that. >> > >> >> >> >> Rich. >> >> >> >> -- >> >> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones >> >> Read my programming and virtualization blog: http://rwmj.wordpress.com >> >> virt-p2v converts physical machines to virtual machines. Boot with a >> >> live CD or over the network (PXE) and turn machines into KVM guests. >> >> http://libguestfs.org/virt-v2v >> > >> > _______________________________________________ >> > Devel mailing list >> > Devel(a)ovirt.org >> > http://lists.ovirt.org/mailman/listinfo/devel _______________________________________________ Devel mailing list Devel(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/devel