Method for storage-less scheduler to enforce "at least once within window" run policy
Publication Date: 2018-Jul-11
The IP.com Prior Art Database
Disclosed is a system for scheduling process that must be run with "at least once"
within specified time window policy. There's no control over execution environment (it
may be not available during part of the window, it can be turned off and then on at any
time). The process should never continue its execution beyond specified time window.
Process manager should keep execution state in memory. If execution
environment is available during the whole-time window, it should run the process at the
beginning of it. In case of execution environment being non-available (information about
previous process execution is lost), process should be run immediately after it becomes
available again, but only if it's still within time window. If process is running, but time
window is about to close, then process manager should stop the process execution.
Described solution has the following benefits: it enforces "at least once" policy
(when job execution time fits the time window minus scheduler downtime), there's no
need for additional job persistent storage and it does not allow job to run indefinitely
(contrary to most schedulers).
As an example, there is a cloud environment with a scheduler module deployed
onto it (as part of larger appliance). Scheduler runs computation of user usage statistics
daily. Time window was selected to be between midnight and 2 am, so there would be
least impact on normal system operations (process should not run after that time,
otherwise users may get longer...