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Comment by derefr | Hacker News Reader

I've never seen a process supervisor daemon that didn't have an "if process FOO exceeds X restarts in Y milliseconds, stop trying to start FOO" clause.

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You've never seen an "enterprise" software init script then. 5-nines? Stick it in an endless loop and no one will notice (Atlassian I'm looking at you).

I have written enterprise software. Guilty as charged.

Yeah, but looking at Atlassian is easy, for pete's sake they gave us shitty software like JIRA, Confluence and others... and I say that with a HUGE dislike of those products due to how obtuse they can be.

Fair point! Agree entirely by the way.

daemontools / supervise doesn't have it and it's a fairly popular solution. (not that I recommend ever using it...)

> daemontools / supervise doesn't have it and it's a fairly popular solution.

Ok, it doesn't exactly support the quoted feature ("stop restarting if it exceeds X attempts in Y seconds"), but it does sleep for a second between restart attempts to mitigate the same problem: http://cr.yp.to/daemontools/supervise.html

I'm curious why you wouldn't recommend it. I've never used it myself, but I've been reading about it the past few weeks. The design seems really well done compared to init.d scripts in the sense that every init script must reimplement daemonization, pid files, etc. (which is helped by examples, start-stop-daemon, etc. but is still a huge and delicate chore in my experience).

Is your objection that daemontools is largely unused / unmaintained and lacks features (such as flapping-avoidance)? Or something else?

Just curious, thanks.

It's mostly about the lack of features. No support for cgroups, user switching, adjustable backoff, syslog, etc. Sure - it works, but it's the same thing as with qmail - it's the very minimum that you can call a useful SMTP deaemon. The moment you want any feature on top, you have to implement it yourself.

Either one of upstart, systemd, supervisord will give you equivalent solution that has more practical features. Daemontools was good enough a couple of years ago. (I used it then happily)

In short - there's nothing wrong with it really, but many alternatives are much better.

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