4 ms·
Two that have stuck with me: A nanosecond is about a foot. A pico second is the size of a flake of pepper. Adm. Grace Hopper gave me a nanosecond back in high
by wiredfool 9y ago
Two that have stuck with me:
A nanosecond is about a foot. A pico second is the size of a flake of pepper.
Adm. Grace Hopper gave me a nanosecond back in high school, and had a pack of picoseconds at the talk. (But didn't give them away. too small)
- dahart 9y agoThat's extra helpful because these units are approximately the speed of light. Light travels a foot in one nanosecond, and it also traverses the width of a (small, ~.01 inch) pepper flake in a picosecond. When I think about light travelling one foot in a nanosecond, it suddenly puts CPU speeds into proportion for me -- CPUs are now routinely clocking 3-4 cycles per light-foot! A foot is a long way in CPU die lengths, but it's surprising to think about how close CPU's are actually getting to the speed of light already.
- AnimalMuppet 9y agoI remember reading (clear back in the late 1970s, in Datamation magazine) how much fun IBM was having trying to make 2 mainframe CPUs operate coherently with sub-nanosecond clock speeds, when the two CPUs were several feet apart. Just from a speed-of-light perspective, the problem is obvious.