One entirely different solution is to move to some kind of process manager (who will guarantee that only one instance runs at a time) and then change your cron entry to tell the process manager to start the task. If the task is already running, the process manager will ignore the redundant request.

For example, if you use docker (which is a process manager in addition to a container manager) you could create a container that starts, performs the job of the script once, and exits. Then your cron command would be “docker start my-task-name”. Other process managers I like are perp, and runit.

In reply to Re: singleton lock not reliable by NERDVANA
in thread singleton lock not reliable by pidloop

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