Date: Mon, 28 Jun 2004 12:06:54 -0700 (PDT) From: Mark Terribile <materribile@yahoo.com> To: freebsd-questions@freebsd.org Subject: Re: Maximum uptime 497 days? Message-ID: <20040628190654.96737.qmail@web21122.mail.yahoo.com> In-Reply-To: <20040628163203.374C216A4E7@hub.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
[Coming in late ...]
> On Mon, Jun 28, 2004 at 05:19:10PM +0400, Maxim Konovalov wrote:
> > On Mon, 28 Jun 2004, 12:39+0900, Rob wrote:
> > > By accident I happen to come across this remarkable limit of
> > > uptime registration for FreeBSD systems. After 497 days, the
> > > timer jumps to zero again.
> > >
> > > 497 days is less than a 1.5 years !
> > >
> > > Has this been fixed in newer versions of FreeBSD (stable and/or
> > > current) ? Or is there a hardware limitation (CPU?) that does
> > > not allow this?
Most system management/statistical things are built around the MIB (Management
Information Base) concept used by SNMP, etc. These call for time to be kept
in 10,000ths of a second in a 32-bit unsigned counter. That register rolls
over in about 497 days. (Later versions of the base MIB add 64-bit counters,
but support isn't universal and software designs tend to prefer the original
counters.)
Mark Terribile
__________________________________
Do you Yahoo!?
New and Improved Yahoo! Mail - Send 10MB messages!
http://promotions.yahoo.com/new_mail
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20040628190654.96737.qmail>