public virtual void TestBackoffDecrease()
{
// when starting a number of process instances process instance
for (var i = 0; i < 15; i++)
{
var id = _engineRule.RuntimeService.StartProcessInstanceByKey("simpleAsyncProcess").Id;
}
// ensure that both acquisition threads acquire the same jobs thereby provoking an optimistic locking exception
JobAcquisitionTestHelper.SuspendInstances(_engineRule.ProcessEngine, 12);
// when starting job execution, both acquisition threads Wait before acquiring something
_jobExecutor1.Start();
_acquisitionThread1.WaitForSync();
_jobExecutor2.Start();
_acquisitionThread2.WaitForSync();
// when continuing acquisition thread 1
// then it is able to acquire and execute all jobs
_acquisitionThread1.MakeContinueAndWaitForSync();
// when continuing acquisition thread 2
// acquisition fails with an OLE
_acquisitionThread2.MakeContinueAndWaitForSync();
_jobExecutor1.Shutdown();
_acquisitionThread1.WaitUntilDone();
_acquisitionThread2.MakeContinueAndWaitForSync();
// such that acquisition thread 2 performs backoff
var jobExecutor2WaitEvents = ((RecordingAcquireJobsRunnable)_jobExecutor2.AcquireJobsRunnable).WaitEvents;
Assert.AreEqual(1, jobExecutor2WaitEvents.Count);
// when in the next cycles acquisition thread2 successfully acquires jobs without OLE for n times
JobAcquisitionTestHelper.ActivateInstances(_engineRule.ProcessEngine, 12);
for (var i = 0; i < BackoffDecreaseThreshold; i++)
{
// backoff has not decreased yet
Assert.True(jobExecutor2WaitEvents[i].TimeBetweenAcquisitions > 0);
_acquisitionThread2.MakeContinueAndWaitForSync(); // acquire
_acquisitionThread2.MakeContinueAndWaitForSync(); // continue after acquisition with next cycle
}
// it decreases its backoff again
var lastBackoff = jobExecutor2WaitEvents[BackoffDecreaseThreshold].TimeBetweenAcquisitions;
Assert.AreEqual(0, lastBackoff);
}
public virtual void TestBackoffOnOptimisticLocking()
{
// when starting a number of process instances process instance
for (var i = 0; i < 9; i++)
{
_engineRule.RuntimeService.StartProcessInstanceByKey("simpleAsyncProcess"); //.Id;
}
// ensure that both acquisition threads acquire the same jobs thereby provoking an optimistic locking exception
JobAcquisitionTestHelper.SuspendInstances(_engineRule.ProcessEngine, 6);
// when starting job execution, both acquisition threads Wait before acquiring something
_jobExecutor1.Start();
_acquisitionThread1.WaitForSync();
_jobExecutor2.Start();
_acquisitionThread2.WaitForSync();
// when having both threads acquire jobs
// then both Wait before committing the acquiring transaction (AcquireJobsCmd)
_acquisitionThread1.MakeContinueAndWaitForSync();
_acquisitionThread2.MakeContinueAndWaitForSync();
// when continuing acquisition thread 1
_acquisitionThread1.MakeContinueAndWaitForSync();
// then it has not performed Waiting since it was able to acquire and execute all jobs
var jobExecutor1WaitEvents = _jobExecutor1.AcquireJobsRunnable.WaitEvents;
Assert.AreEqual(1, jobExecutor1WaitEvents.Count);
Assert.AreEqual(0, jobExecutor1WaitEvents.ElementAt(0).TimeBetweenAcquisitions);
// when continuing acquisition thread 2, acquisition fails with an OLE
_acquisitionThread2.MakeContinueAndWaitForSync();
// and has performed backoff
var jobExecutor2WaitEvents = _jobExecutor2.AcquireJobsRunnable.WaitEvents;
Assert.AreEqual(1, jobExecutor2WaitEvents.Count);
var waitEvent = jobExecutor2WaitEvents.ElementAt(0);
// we don't know the exact Wait time,
// since there is random jitter applied
JobAcquisitionTestHelper.AssertInBetween(BaseBackoffTime, BaseBackoffTime + BaseBackoffTime / 2, waitEvent.TimeBetweenAcquisitions);
// when performing another cycle of acquisition
JobAcquisitionTestHelper.ActivateInstances(_engineRule.ProcessEngine, 6);
_acquisitionThread1.MakeContinueAndWaitForSync();
_acquisitionThread2.MakeContinueAndWaitForSync();
// and thread 1 again acquires all jobs successfully
_acquisitionThread1.MakeContinueAndWaitForSync();
// while thread 2 again fails with OLE
_acquisitionThread2.MakeContinueAndWaitForSync();
// then thread 1 has tried to acquired 3 jobs again
var jobExecutor1AcquisitionEvents = _jobExecutor1.AcquireJobsRunnable.AcquisitionEvents;
var secondAcquisitionAttempt = jobExecutor1AcquisitionEvents.ElementAt(1);
Assert.AreEqual(3, secondAcquisitionAttempt.NumJobsToAcquire);
// and not Waited
jobExecutor1WaitEvents = _jobExecutor1.AcquireJobsRunnable.WaitEvents;
Assert.AreEqual(2, jobExecutor1WaitEvents.Count);
Assert.AreEqual(0, jobExecutor1WaitEvents.ElementAt(1).TimeBetweenAcquisitions);
// then thread 2 has tried to acquire 6 jobs this time
var jobExecutor2AcquisitionEvents = _jobExecutor2.AcquireJobsRunnable.AcquisitionEvents;
secondAcquisitionAttempt = jobExecutor2AcquisitionEvents.ElementAt(1);
Assert.AreEqual(6, secondAcquisitionAttempt.NumJobsToAcquire);
// and again increased its backoff
jobExecutor2WaitEvents = _jobExecutor2.AcquireJobsRunnable.WaitEvents;
Assert.AreEqual(2, jobExecutor2WaitEvents.Count);
var secondWaitEvent = jobExecutor2WaitEvents.ElementAt(1);
long expectedBackoffTime = BaseBackoffTime * BackoffFactor; // 1000 * 2^1
JobAcquisitionTestHelper.AssertInBetween(expectedBackoffTime, expectedBackoffTime + expectedBackoffTime / 2, secondWaitEvent.TimeBetweenAcquisitions);
}