Project: datamanagement
Issue DM-2694: Revisit mysql connections from worker
Revisit the code that handles mysql connections in qserv. At the moment Qserv will maintain a connection per chunk-query, up to a hardcoded limit (GroupScheduler: 4, ScanScheduler:32). Also, we have to gracefully handle connection issues (such as dropped connection, or if we hit the max_connections limit).
Story points: 8