to, 2006-06-08 kello 12:20 -0700, Tyler MacDonald kirjoitti: > Sebastian Harl <[EMAIL PROTECTED]> wrote: > > > http://www.crackerjack.net/adserton3.png > > > > On that picture it says the box is up for 378 days. How does that go with > > 875 days idle time? > > > > Due to a bug with "w", or the kernel, or whatever, which nobody seems to > want to fix, the system uptime wraps around to 0 days after 400-and-someodd > days. That's why I circled the login/idle time on the screenshot. :-)
If I've understood correctly, uptime in the kernel is counted by an unsigned integer that is 32 bits on most platforms (64 bits on the 64 bits ones, I assume). It counts "jiffies", which typically happen 100 times a second. 32^2 jiffies divided by (100 times/second * 24 * 60 * 60 seconds) is about 497 days. 875 - 378 = 497. Fixing this would require having every increment of the jiffies counter to check for overflow, and using two counters. This is unnecessary overhead (a very small overhead, granted, but still), for a very small benefit. -- I am a werehuman. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
