Can't kill hung remote CP copy

[suvayu ali]

On Fri, Apr 13, 2012 at 15:22, Kevin Martin <kevintm at ameritech.net> wrote:
>
>
> On 04/13/2012 05:55 AM, suvayu ali wrote:
>> On Fri, Apr 13, 2012 at 11:47, Reindl Harald <h.reindl at thelounge.net> wrote:
>>>> How can I kill the broken cp operation ?
>>> killall -s SIGKILL cp
>> This might not work always. I have faced similar issues with processes
>> waiting to access a filesystem over the network. In these cases if there
>> is a problem with the network it might get into an UNINTERRUPTIBLE SLEEP
>> since it is waiting for I/O. The only way to get rid of these processes
>> is to wait or reboot. In my case this was a tape drive over a network
>> filesystem.
>>
>> The OP can check if this is indeed the case by doing
>>
>>   $ ps uf
>>
>> If the "cp" process is in UNINTERRUPTIBLE SLEEP, the STATE of the
>> process should be D. If not then you can ignore my comment.
>>
> What happens if you ifdown the nic (if you are on the console
> obviously)?  Would that allow the cif mount and/or the cp to become
> available for umount/kill?

That is a good question. I don't know what would happen then. I guess if
the filesystem implementation is smart enough to return an error when
the network goes down, then the I/O wait is over and the application
gets file read error of some kind and "wakes up" from its
UNINTERRUPTIBLE SLEEP. But then, this is just a hypothesis which I
cannot test (I do not have admin privileges to test this).

-- 
Suvayu

Open source is the future. It sets us free.