Dave Jones’ post reminded me that tonight we have a leap second. 23:59:59 will be followed by 23:59:60. Wikipedia saves me the trouble of explaining why:
Leap seconds are necessary because time is measured using stable atomic clocks (TAI or International Atomic Time), whereas the rotation of Earth slows down continually, though at a slightly variable rate. Originally, the second was defined as 1/86400 of a mean solar day (see solar time) as determined by the rotation of the Earth around its axis. By the middle of the 20th century it was apparent that the rotation of the Earth did not provide a sufficiently uniform time standard and in 1956 the second was redefined in terms of the annual orbital revolution of the Earth around the Sun. In 1967 the second was redefined, once again, in terms of a physical property: the oscillations of an atom of Caesium-133, which were measurable by an atomic clock. But the solar day becomes 1.7 ms longer every century due mainly to tidal friction (2.3 ms/cy, reduced by 0.6 ms/cy due to glacial rebound).
Mr. Jones’ blog post has a different point, though. Tonight all of our servers are going to run a section of code that gets used very rarely, and as such really isn’t time-tested:
This all sounds fairly benign, but it has been known to be problematic. For reasons I’m not entirely sure of, ntp still calls into the kernel twice a year, regardless of whether a leap second is inserted or not. So, twice a year, we end up in different code paths that we don’t execute the rest of the year.
I wonder how many rarely-used code paths there are like this, in drivers, in kernels, in databases and software, quietly rotting until they get triggered one day, and then everything comes crashing down. It sure makes efforts like automatic crash dump reporting seem useful, because us system administrator types reboot the machines, restart the software, and wait for it to happen again. And it doesn’t. Or if it does we don’t correlate it with the last crash, because that was two years ago. It’s also a big selling point for unit testing.
At any rate, may all your pagers and cell phones stay quiet all night long. Enjoy New Year’s Eve and Day, and stay safe.
This is probably real old news, but I just saw the Mr. T “I am the T in I.T.” video from Hitachi today. Corny, no doubt, but lines like “intelligence in the network is for suckas” make me laugh.
My goal for next week is to use “I’m gonna virtualize you fools” in conversation at least once.
This is pretty neat. The animals will be able to move around between the Apostle Islands and the mainland (which basically just means the wolves will shuffle around some).
"Advocacy groups working to combat drunk driving worry that the iBreath might promote binge drinking and create a false sense of security." As my friend Bob points out we should ban speedometers, because knowledge of one's speed might lead to people seeing how fast they can go. I'm not an advocate of drunk driving but I think MADD is just a bunch of crazy prudes f-ing it up for the rest of the world who are responsible drivers.
"Sweeney ran his refrigerator, freezer, TV, woodstove fan, and several lights through his Prius, for three days, on roughly five gallons of gas." Priuses are pretty cool like that, rolling generators and battery packs.
"Sun should be prepared to give up on SPARC." Yes. Ditch SPARC and start making good decisions, about a lot of things. Sun is adrift and before they have to make really tough choices later they should make some pretty hard ones now.
Alex King blogs about his choice of a Dell monitor vs. an Apple one. It's interesting, and I think it's something Apple is going to have to watch closely. People aren't going to go for Apple gear when it's twice the price and fewer features, no matter what it looks like.
Took your faucet’s aerator apart to clean it? Trying to figure out how to put it back together again? Internet absolutely no help because it tells you that you should have noted how it came out in the first place? Yeah, I’m with you, pal, and you’ve come to the right place. This is how. Click on the photos for larger versions.
First, I numbered everything so I could refer to them (this is also the order they go back into #1):
The part I got hung up on was where you put part #3 into part #2 first, because it seems like it’d block all the water. It goes in like this:
Then stick that in part #1:
Top it all off with part #4:
Put part #5 on top, screw it all back into the faucet, and you’re done.
