13.37, Friday 4 Feb 2011 Link to this post
There's a lovely collection of numbers from Jeff Dean at Google, about how long common computer processor and network operations take. Data on the same chip takes, at its quickest, only 0.5ns to look up (half a billionth of one second). Data in computer memory takes 100ns (200 times as long) to pull onto the chip. Data in the same building takes a million times as long; data across the Atlantic will take 300 millions times as long. Here are the numbers.
What makes this more human is this comparison, which reveals a little bit about computer time: your equivalent to a computer looking up data from a chip is remembering a fact from your own brain. Your equivalent to a computer looking up data from a disk is fetching that fact from Pluto. Computers live in a world of commonplace interactions not the size of a house, like us, but the Solar System. On their own terms, they are long, long lived, and vast.