Hi, thanks for posting.

The analysis task is a test discovery action. It involves creating a runtime environment (i.e. launching your code using the CLR and loading the assembly), then asking the test framework for details about the tests contained in the assembly. There is no relationship between this task and roslyn analysers (it was actually introduced years before Roslyn even existed in any public form).

The performance of this task is directly dependent on the performance of the testing framework you are using. Test frameworks such as NUnit and XUnit can be quite complex during test discovery as they build an in-memory model of your tests using reflection. If you want NCrunch to be able to execute your tests, there is no way to skip this task.

Later in the queue NCrunch will use the same runtime environment to execute your tests. This means that if there were a way to prevent this task from being run, the work being done would simply move to the execution tasks instead.

Distributed Processing will be of very limited help here, because we presently don't distribute the analysis task in the same way as the test tasks. Right now the analysis task will run on each node (we have plans to change this eventually).

Upgrading your hardware will usually help.

It may also be possible to redesign your test suite to reduce the cost of test discovery. I'm not really an expect on the behaviour of the internals of Xunit, but I would expect that more complex constructions such as Theories will probably require more CPU to discover by the framework. Reducing your overall number of tests will improve discovery time. If the option is available, you could also try different test frameworks to see which ones will perform better for your solution. MSTest usually gives the best performance under NCrunch because this is run under optimised emulation (rather than being directly integrated).

I've just learned, that MSTest has the same concept as xUnit Theories:

[DataRow(0, 0)]
[DataRow(1, 1)]
[DataRow(2, 1)]
[DataRow(80, 23416728348467685)]
[DataTestMethod]
public void MyTest(int number, int result)
{
// do something
}

I've also observed, that NCrunch does not have any "Analysis Task" when using MSTest. This explains why I've never seen it during the last 8 Years of NCrunch usage, but now suddenly (since I'am playing around with xUnit) it showed up :)

Before using xUnit, I consulted https://www.ncrunch.net/support/frameworks. Maybe it is a good idea to add a hint on ncrunch runtime perforamance for the single test frameworks. This might help others no not learn it the hard way as I diD.