What? You don’t think Travis can run these fast?
> On Sep 15, 2017, at 2:07 PM, Galen O'Sullivan <gosulli...@pivotal.io> wrote:
>
> +1 This is great! I'll take a look at your PR when I get the time.
>
> We may want to think carefully about how often we run these tests, because
> unlike regular unit tests, they will take forever to run.
>
> On Fri, Sep 15, 2017 at 1:42 PM, Michael William Dodge <mdo...@pivotal.io>
> wrote:
>
>> +1 for unit tests for multithreaded code.
>>
>> High fives to Dan.
>>
>> Sarge
>>
>>> On 15 Sep, 2017, at 12:08, Dan Smith <dsm...@pivotal.io> wrote:
>>>
>>> Hi Geode devs,
>>>
>>> I've been messing around with an open source tool called Java
>>> Pathfinder for writing tests of multithreaded code. Java Pathfinder is
>>> a special JVM which among other things tries to execute your code
>>> using all possible thread interleavings.
>>>
>>> I'd like to propose two things:
>>>
>>> 1) We introduce a framework for writing unit tests of code that is
>>> supposed to be thread safe. This framework should let a developer
>>> easily write a test with multiple things going on in parallel. The
>>> framework can then take that code and try to run it with different
>>> thread interleavings.
>>>
>>> Here's an example of what this could look like:
>>>
>>> @RunWith(ConcurrentTestRunner.class)
>>> public class AtomicIntegerTest {
>>>
>>> @Test
>>> public void parallelIncrementReturns2(ParallelExecutor executor)
>>> throws ExecutionException, InterruptedException {
>>> AtomicInteger atomicInteger = new AtomicInteger();
>>> executor.inParallel(() -> atomicInteger.incrementAndGet());
>>> executor.inParallel(() -> atomicInteger.incrementAndGet());
>>> executor.execute();
>>> assertEquals(2, atomicInteger.get());
>>> }
>>>
>>>
>>> 2) We implement this framework initially using Java Pathfinder, but
>>> allow for other methods of testing the code to be plugged in for
>>> example just running the test in the loop. Java pathfinder is cool
>>> because it can run the code with different interleavings but it does
>>> have some serious limitations.
>>>
>>> I've put together some code for this proposal which is available in
>>> this github PR:
>>>
>>> https://github.com/apache/geode/pull/787
>>>
>>> What do you think?
>>>
>>> -Dan
>>
>>
