Re: uptime reset after about 45 days

Maciej Zenczykowski
2003-10-30T23:09:45Z

> After about 45 days or so, my uptime was reset. My idle time is correct.
>
> $ cat /proc/uptime
> 94245.37 3686026.54
>
> $ cat /proc/version Linux version 2.4.20-gentoo-r1
> (root@dpb2.resnet.calvin.edu) (gcc version 3.2.2) #6 SMP Thu Apr 17
> 14:11:34 EDT 2003

Uptime is stored in jiffies which is 32bit on your arch, which results in
an overflow after 2^32 clock ticks. TTTicks were 100 HZ till recently
(overflow after 470 or so days) now, they're 1000 -> overflows after 45
days. Doesn't wreck anything except for uptime display - known problem,
not worth the trouble fixing it would cause (64 bit values are
non-atomic, unless MMX/SSE which isn't allowed in kernel) - however there
is (if I'm not mistaken) a patch available wihich fixes this 'problem'.

However since it is only a matter of uptime display...

Cheers,
MaZe.