[Haskell-cafe] Re: System.CPUTime and picoseconds

Manlio Perillo wrote:

Hi.

Just out of curiosity, but why Haskell 98 System.CPUTime library module uses picoseconds instead of, say, nanoseconds?

At least on POSIX systems, picoseconds precision is *never* specified.

I have not idea. But at a guess, I would say that 1 ns is not such a small time interval anymore. The CPU speeds are about 3 GHz, so 0.3 ns per CPU clock. Even the RAM clock in a laptop (e.g. Apple's 17" Mac Pro) is 1066 MHz, so the internal there is just under 1 ns. Whoever picked picoseconds has made it possible to talk about a single clock interval for hardware like this. -- Chris