Re: Jiffies Wraparound (was Re: interrupt counts) (fwd)

Theodore Y. Ts'o (
Tue, 20 Aug 1996 16:23:53 -0400

From: Jim Nance <>
Date: Tue, 20 Aug 1996 07:10:08 -0400 (EDT)

Its not supposed to break anything, but I doubt it has ever been tested.
Something that might be interesting is to compile a kernel with the counter
pre-initialized so that it will overflow in about 5 minutes. Then some
network connections, compilers, etc. could be started up, and we could
see what happened when it overflowed.

Something that would probably be a very good thing to do is during the
2.1 development cycle, change the kernel so that jiffies *always*
overflows after 5 minutes. It would be a very good way of making sure
that we can always handle the overflows correctly, and it's also a good
way to keep future device driver developers on the straight and narrow.

- Ted