[Haskell-cafe] thread killed

tsuraan tsuraan at gmail.com
Wed Apr 4 16:52:26 CEST 2012

> That's probably not where the threadKill is being sent *from*, it's where
> your thread received it.

Yeah, it's definitely where my thread received it.  It's just sort of
crazy, because when I get a ThreadKilled, it's almost always in
Tiger.update.  My handler does much slower things, such as connecting
to a database and doing operations that can take tens of milliseconds,
but somehow the ThreadKilled nearly always emanates from my
Tiger.update.  I even went so far as to wrap my Tiger.update in an IO
operation that catches the ThreadKilled and tries the update again,
and that "fixed" upwards of 90% of my thread deaths.  Crazy...

> It's hard to rule Snap timeouts out; try building snap-core with the
> "-fdebug" flag and running your app with "DEBUG=1", you'll get a spew of
> debugging output from Snap on stderr.

I'll give that a try, but whenever I've added any sort of printing to
my handler to try to track things down, the issue goes away entirely.
My toolkit for debugging race conditions is pretty weak; I usually
have been able to think real hard and then fix them intuitively, but
my intuition about Haskell is still weak enough that my normal
approach isn't working :)

More information about the Haskell-Cafe mailing list