Re: ps shows same process more than once

["George M. Florendo" <georgeflorendo@gmail.com>]

On 11/29/13, Christopher Faylor wrote:
> On Thu, Nov 28, 2013 at 10:55:04AM -0500, Christopher Faylor wrote:
>>On Thu, Nov 28, 2013 at 02:08:13PM +0100, Corinna Vinschen wrote:
>>>On Nov 28 15:20, George M. Florendo wrote:
>>>> Hi,
>>>>
>>>> I run a non cygwin apache process named httpd.exe.  Checking it with
>>>> "ps -W" shows a listing of the same process (with PID 4560 in this
>>>> case) twice.
>>>>
>>>> $ ps -W | grep httpd
>>>>      4560    1604    4560       5304  pty0    1000 09:55:21
>>>> /home/georgeflorendo/wamp/bin/apache/Apache2.4.4/bin/httpd
>>>>      4560    1604    4560       5304  pty0    1000 09:55:21
>>>> /home/georgeflorendo/wamp/bin/apache/Apache2.4.4/bin/httpd
>>>>      7508       0       0       7508  ?          0 15:09:50
>>>> C:\cygwin\home\georgeflorendo\wamp\bin\apache\Apache2.4.4\bin\httpd.exe
>>>>
>>>> Doing a "ps aux" shows it only once.
>>>>
>>>> $ ps aux
>>>>       PID    PPID    PGID     WINPID   TTY     UID    STIME COMMAND
>>>>      1340    7856    1340       5720  pty5    1000 15:13:50 /usr/bin/ps
>>>>      1604    4008    1604       2292  pty0    1000 09:17:01
>>>> /usr/bin/bash
>>>>      4008       1    4008       4008  ?       1000 09:17:00
>>>> /usr/bin/mintty
>>>>      4560    1604    4560       5304  pty0    1000 09:55:21
>>>> /home/georgeflorendo/wamp/bin/apache/Apache2.4.4/bin/httpd
>>>>
>>>> <snipped>
>>>>
>>>> Is it correct that ps -W shows the same process twice?
>>>
>>>Not exactly but it could happen.  Can you try the latest snapshot Cygwin
>>>DLL from http://cygwin.com/snapshots/ and see if it fixes the problem?
>>
>>I don't see anything in the ChangeLog which would affect this and I'd
>>be concerned if there was.
>>
>>There are scenarios where two different windows pids can be associated
>>with the same Cygwin pid.  You should only see it when you do a "ps -W".
>>
>>So, AFAICT, the correct answer to the "Is it correct" is "Yes'.
>
> Oops.  Sorry.  Just noticed that the pids weren't "different".  There
> are still pathological situations where a pid can show up twice when
> doing a "ps -W".  I've seen the issue before but fixing it would involve
> a global process lock which would slow down Cygwin for the benefit of
> a more accurate "ps -W".

Oh, I'm sorry too.  Didn't get to read your first sentence earlier.
I'd rather have a faster cygwin more than a more accurate "ps -W".

Thanks for all your help.
-- 
George M. Florendo
Programmer
http://www.facebook.com/i.am.georgeflorendo

--
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