RFR: 7187882: TEST_BUG: java/rmi/activation/checkusage/CheckUsage.java fails intermittently

[Stuart Marks]

(Note for other readers: StreamPipe is not part of this webrev; the source is 
viewable at [1].)

Hi Mandy,

I don't see any place where the StreamPipe threads are interrupted, so the 
silent exit on InterruptedIOException probably doesn't ever get exercised. This 
handling does seem a bit odd to me though.

For both IOException and InterruptedIOE the thread exits immediately (and for 
IOE a stack trace is printed) but this is never reported to the caller, so if 
one of these did occur, it's likely that no one would ever notice -- unless it 
caused the calling test to fail. It would probably be reasonable for a 
StreamPipe to store an indication of whether it encountered and exception and 
have code in JavaVM.waitFor query it and report it to the caller. This seems 
like a pretty rare case though. Maybe something to do in a future cleanup.

Turns out this bug was pretty easy to reproduce by putting a sleep() at the 
right place in the StreamPipe loop. This causes the StreamPipe always to "lose" 
the race condition so in the old code the test would fail every time. With the 
new join() logic the test always passes, even with sleep() in place; it just 
runs more slowly.

Thanks,

s'marks




[1] 
http://hg.openjdk.java.net/jdk8/tl/jdk/file/a996b57e5541/test/java/rmi/testlibrary/StreamPipe.java



On 1/4/13 4:38 PM, Mandy Chung wrote:
> It is a good cleanup and the change looks okay to me.  I'll count on your
> testing to verify if this fixes the intermittent problem :)
>
> StreamPipe.run() catches InterruptedIOException and IOException and ignores the
> error.  Is it safe?  Are the tests expected to fail in some other way (missing
> output?).  Should it (or waitFor method) throw a RuntimeException instead if
> any such exception is thrown?
>
> Just curious - Is this intermittent test failure easy to reproduce?
>
> Thanks
> Mandy
>
> On 1/3/2013 6:39 PM, Stuart Marks wrote:
>>
>> Hi all,
>>
>> Please review these additional RMI test cleanups:
>>
>> http://cr.openjdk.java.net/~smarks/reviews/7187882/webrev.0/
>>
>> in service of fixing the following bug:
>>
>> http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7187882
>>
>> The basic problem here is that tests were waiting for the JVM subprocess to
>> exit, but not waiting for all output from the subprocess to be collected. The
>> fix includes a bit of new infrastructure in RMI's test library and adjustment
>> of several other tests to use it.
>>
>> Thanks,
>>
>> s'marks