[racket-dev] [DrDr] R25887 (timeout 1) (unclean 1) (stderr 1) (changes 64)

On Wed, Dec 12, 2012 at 11:51 AM, Sam Tobin-Hochstadt <samth at ccs.neu.edu> wrote:
> On Wed, Dec 12, 2012 at 1:44 PM, Jay McCarthy <jay at cs.byu.edu> wrote:
>> On Tue, Dec 11, 2012 at 1:01 PM, Sam Tobin-Hochstadt <samth at ccs.neu.edu> wrote:
>>> The Typed Racket optimizer tests continue to fail on an intermittent
>>> basis in DrDr, as shown below.  I'd really like to fix this,
>>> especially since we're doing very well for zero failures on DrDr, but
>>> I don't know what's going wrong.
>>>
>>> The error is:
>>>
>>> force: promise's thread terminated without result or exception
>>>   promise: #<promise:!running!...et/optimizer/run.rkt:47:28>
>>>   context...:
>>>    /opt/plt/builds/<current-rev>/trunk/collects/racket/promise.rkt:98:2
>>>    /opt/plt/builds/<current-rev>/trunk/collects/tests/typed-racket/optimizer/run.rkt:50:3:
>>> for-loop
>>>    /opt/plt/builds/<current-rev>/trunk/collects/tests/typed-racket/optimizer/run.rkt:44:0:
>>> mk-suite
>>>
>>> which I think indicates that a thread is being killed somewhere, but I
>>> don't know why that would be happening, and I haven't seen this
>>> happening on other machines.
>>>
>>> Are there any techniques recommending for finding what's killing this
>>> thread?  Does DrDr do anything special that would affect this?  The
>>> relevant code is here:
>>> https://github.com/plt/racket/blob/master/collects/tests/typed-racket/optimizer/run.rkt#L44-53
>>
>> There are two cases were DrDr kills stuff. Case 1 is when there's a
>> timeout, but you aren't close to that. Case 2 is when DrDr itself
>> crashes and needs to get a clean slate of system resources. I think
>> this is unlikely to be the problem, because the DrDr instance that
>> crashed would be the one listening to the test's output not the one
>> that did the killing. But I can look into it.
>
> Given that this happens quite regularly (maybe 1 in 5 runs) I'd be
> surprised if DrDr itself crashed that often.  Is that likely?

DrDr crashes very often, almost every push. This is mainly because the
X setup I use is unreliable, crashes, and then I have to tear down all
of DrDr to get back to a consistent state. DrDr is designed around
crashing often as a way of dealing with this problem (and a few other
similar ones.)

Jay

--
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://faculty.cs.byu.edu/~jay

"The glory of God is Intelligence" - D&C 93