Running a nonblocking conductor or two conductors on the same host will re-execute the same job multiple times with the current implementation of 'claim' for the redis jobboard backend. This is different from the ZooKeeper jobboard backend, there the same owner of a job is not allowed to reclaim the job again (https://github.com/openstack/taskflow/blob/master/taskflow/jobs/backends/impl_zookeeper.py#L554). If the same owner is allowed to reclaim the job again there can be no concurrent execution on the same owner because all jobs will be re-claimed and re-executed by the same owner every pass as long as it's on the jobboard.
To reproduce this behavior:
- Use the redis jobboard backend
- Create a flow with a task that sleeps 10 seconds in the execute method
- Post that flow as a job
- Run a nonblocking conductor
It will claim and execute the same job multiple times in a loop until the first worker is finished and consumes the job. After this change it will not re-execute the same job multiple times.
Change-Id: I4f6c364211500e510fc496f23b03ce056771417d
5f3c132523