UNIXProcess improvements

[Michael McMahon]

Martin,

Thanks for the answers. The changes look fine to me.

- Michael.

Martin Buchholz wrote:
> On Mon, Apr 19, 2010 at 09:04, Michael McMahon <Michael.McMahon at sun.com> wrote:
>   
>> Martin Buchholz wrote:
>>     
>>> On Fri, Apr 16, 2010 at 09:18, Mark Reinhold <mr at sun.com> wrote:
>>>
>>>
>>>       
>>>> For now I suggest leaving old @author tags as-is.
>>>>
>>>>         
>>> OK, done.
>>>
>>> Version 0.2 of the webrev is published.
>>>
>>> Martin
>>>
>>>       
>> Martin,
>>
>> From what I can see, you've cleaned up the code and the functional changes
>> are the use of a thread pool, and an explicit (8 k sized) stack.
>>     
>
> Exceptions thrown in the "process reaper" thread,
> which were not IOExceptions,
> were not being caught, and would cause the user thread to hang.
>
>   
>> Also, the threads created now belong to the root thread group rather than
>> the application's thread group.
>>     
>
> Well, they have to belong to some thread group,
> and they get reused, so in general the thread group will have
> no relation to the thread group of the user thread,
> so may as well use the root thread group.
> I stole this technique from elsewhere in the JDK.
>
>   
>> Is this so you can handle uncaught
>> exceptions
>> as you mentioned before, and if so, I guess some other change is coming to
>> complete
>> this work. Is that right?
>>     
>
> Yes.  This change by itself is a clear win,
> except that because it is more memory efficient,
> GC is less likely to get called,
> which means file descriptors of defunct processes
> are less likely to get cleaned up in the face of
> lazy user code, which means it is more subject
> to file descriptor exhaustion problems.
> Which I would like to fix.
>
> Martin
>
>   
>> Thanks,
>> Michael
>>
>>
>>