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Re: Keeping children alive persistiently, intelligentlyby dynamo (Chaplain)
|on Feb 08, 2008 at 19:45 UTC
Ok.. well, first off you'll need to save some (persistent) state. You could do this in files, variables in the parent process, environment variables, whatever.
The first thing that comes to mind is to start off just making a folder for the info, and have each child create a log file named after it's pid, with it's arguments, a log of recent restarts (say, the last 5 min,).
I'd also have each process touch it's pid file every 10 seconds or so, so the parent which is polling the data can know that a pid file not touched in the last 30 seconds needs to have it's child killed and restarted a minute or so later.
Once you have the logic in for restarted dead/stopped children, it's just a matter of adding conditionals and changing the sleep time for the 5 minute stop. Similarly the custom processes will just take an additional conditional checking on the restart history.
Hope that helps,