Serious performance degradation after upgrade from 7.5 to 8.1

I just updated our SQ instance from 7.5 to 8.1.
And now I’m seeing a serious performance degradation.
With 7.5 the analysis took about 2 hours.
Now with 8.1, the analysis takes more than 4 hours.
As far as I can see, the most time that is consumed additionally is spent during Java Main Files AST scan, where for example a module with 1150 files needed about 3 minutes for this task in 7.5 and needs more than 20 minutes now with 8.1.
Or another module with about 4000 files needed about 5 minutes in 7.5 and now needs about 30 minutes with 8.1.

The difference between the cumulated tasks in 7.5 and in 8.1 actually is 2.9 hours, so actually other tasks seem to be faster and it really is the Java Main Files AST scan that needs so much more time.


We’re aware of the issue & started a sprint today to improve it.