31 Mar
2004
31 Mar
'04
2:45 p.m.
Arve Knudsen <aknuds-1(a)broadpark.no> writes:
True .. That was one approach I considered originally
while sketching
up solutions, I guess it slipped my mind in the meantime :| I was
thinking it could possibly be an expensive operation though as NPTL
sources seem to indicate, maybe best avoided if memory locks are
involved (I'm no optimization guru, I'm sure you can tell).
It doesn't look all that expensive. The magic is done by a platform-
dependent compare-and-swap operation. On some SMP machines that can
be slow, but generally only in high-contention situations (AFAIK).
Anyway, do you think it would be good to keep a canary
around to act
on CPU starvation?
Personally, I don't see much need for a canary thread. Others may
disagree. But, a watchdog is quite helpful for debugging. In some
cases, the application will provide its own watchdog. Is it possible
for that thread to be optional?
--
joq