Summary:
The long running stress test had a subtle race condition which caused the test
to fail with an error message like "Runner X edges creation failed because of:
Can't serialize due to concurrent operations.". This situation was caused
because some workers could complete their initialization (initial vertex and
edge creation) before other workers. The workers that completed their
initialization would then proceed to execute the test. In the test they could
execute queries that make global updates on the graph that could interfere with
the concurrently running initialization queries of other workers.
This diff makes the runners wait until all initialization queries are fully
executed before they execute global operations on the graph.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2647
84a6ab75cb