On Mon, 8 Sep 2003, Markus Gaugusch wrote:
On Sep 8, mailinglists
wrote: my primary dns server was up for 500 days. Now I see in top that it's been up for only 3 days. No trace of reboot neither in messages nor in last log. Does top start over at 0 if a certain amount of up-days have been reached? Or how do I have to interprete that? I think there is an overflow at around 480 days. Look at /proc/uptime, maybe there is another value there.
Linux counts time in jiffies (usually 1/100 sec on kernel 2.4, 1/1024 sec on 2.6), and on a 32bit system this counter wraps around after 42949672.96 sec or in other words: 497 days, 2 hours, 27 minutes and 52.96 seconds. This 'problem' is tackled in the 2.6 kernel (where it happens after about 50 days), but it goes away as soon as you use a 64bit system... BTW: there is a slight chance that the computer might crash during the 10msec when jiffies==0, so you were a bit lucky that your server is still up and running. Ciao, Roland +---------------------------+-------------------------+ | TU Muenchen | | | Physik-Department E18 | Raum 3558 | | James-Franck-Str. | Telefon 089/289-12592 | | 85747 Garching | Telefax 089/289-12570 | +---------------------------+-------------------------+