Re: interrupt counts

Mikael Abrahamsson (
Mon, 19 Aug 1996 09:10:04 +0200 (MET DST)

On Mon, 19 Aug 1996, Linus Torvalds wrote:

> On Mon, 19 Aug 1996, Jon Lewis wrote:
> >
> > Just out of curiosity, what's going to happen in about 2 months when my
> > irq 11 counter hits 4294967296? Will it happily wrap, or are things
> > likely to get upset?
> It will happily wrap. The kernel doesn't actually _use_ the interrupt counts
> for anything, they are there only for statistics.

Yes, the same way IP-accounting wrapps pretty quickly as well. 4 gigs over
a net isnt a lot today. Is this perhaps something that should be
considered for 2.1, to convert more and more of these
on-busy-machines-will-wrap-within-a-year counters into 64bit ones? I mean,
as speed of machines goes up all the time, wouldnt it be nice to be ahead
for a while?

Reminds me of Suns "fix" for the problem that the uptime-counter wraps at
256 days uptime. "Reset the machine at around 250 days uptime".. Great fix