RFR 8010182: Thread safety of Thread get/setName()

[Chris Hegarty]

On 05/21/2013 06:07 AM, Mike Duigou wrote:
> Looks good.
>
> Since the char array is never modified it could use the String(char[], boolean) constructor. This has advantages for cases such as logging which may read the thread name very many times.

Thanks Mike, this would be a nice improvement.

Final webrev:
   http://cr.openjdk.java.net/~chegar/8010182/webrev.01/webrev/

-Chris.

>
> Mike
>
> On May 18 2013, at 00:57 , Chris Hegarty wrote:
>
>> Thread getName and setName are not thread-safe. The "expected" usage is to set a name before starting the thread and only read it thereafter.
>>
>> It is desirable to support the setting of thread name dynamically, mainly for monitoring/management/debugging. The typical scenario is the single-writer, multiple-reader case. So, making name volatile is sufficient. However, setName also sets the native thread name. This is currently restricted to the current thread, since there could be a race if the thread is terminating. Making setName synchronized would eliminate that race, and allow for the native thread name to be set from other threads.
>>
>> This issue came up on c-i a while back [1].
>>
>> http://cr.openjdk.java.net/~chegar/8010182/webrev.00/webrev/
>>
>> -Chris.
>>
>> [1] http://cs.oswego.edu/pipermail/concurrency-interest/2013-March/010935.html
>