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A comment on The Common Lisp Condition System – Upcoming Book. Parent comment

Re:The Common Lisp Condition System – Upcoming Book by phoe-krk on Wednesday July 15, 2020 @12:22PM (#23847488)
> You can't quite stash the condition in a database and wait until everyone returns from the holiday to resume progress, but that's merely a technical limitation of the normal lisp compilers that are currently available.

I think that in a multithreaded environment you can try to hang a particular thread by forcing it into the debugger in order to preserve all stack information inside it, but I don't know if that is feasible in the long run on production systems since it opens a gate to possibly DoSing the machine.

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Re:The Common Lisp Condition System – Upcoming Book by lonjil on Wednesday July 15, 2020 @01:04PM (#23848094)
Maybe that would be feasible with lighter weight green threads.

I do this with threads but my system is just a chat bot, so it doesn't really ever turn into a problem.

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Re:The Common Lisp Condition System – Upcoming Book by phoe-krk on Wednesday July 15, 2020 @01:07PM (#23848138)
That would definitely be very feasible with Erlang-style processes, but contemporary Common Lisp implementations do not come equipped with those.
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Re:The Common Lisp Condition System – Upcoming Book by db48x on Wednesday July 15, 2020 @12:59PM (#23848020)
Or just have it wait for an RPC message. A thread waiting on IO doesn't cost much, and you can always spin up more to do the work it was supposed to be doing.

But yea, conditions weren't designed from the start with distributed systems in mind, so you almost need a runtime that can save a whole thread to disk and recover it later. Back in the day though you could just open a window and ask the user what to do directly.

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Re:The Common Lisp Condition System – Upcoming Book by phoe-krk on Wednesday July 15, 2020 @01:08PM (#23848167)
> and you can always spin up more

I think it depends on your OS. IIRC, on Windows, it was fairly easy to destabilize the OS by spawning threads in a loop and starving other processes on the system. I haven't used Windows in a long while though, so I cannot say for sure.

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