Comment 4 for bug 1783405

Yes, there are many tests which taking more times since couple of weeks.

I have prepared the ethercalc and collected the tests which are taking > 100 sec runtime. Collected the Avg time taken since last 14 days. Based on that data we all can mark our voting to make them 'slow' test.
 - https://ethercalc.openstack.org/dorupfz6s9qt

As you mentioned in Bug, API test also taking too much time so there is no issue to mark them 'slow' if required.