Calculates a diff in milliseconds between invocations. Originally I wanted to use process.hrtime, but it looks like Date.now is faster since it doesn't need any conversion.
const start = require('hrtime-milliseconds')
// Create an instance
const diff = start()
// Then invoke the returned function to get the time since its' creation
// It returns an integer that defines how many milliseconds passed (here it's 0 as we're in the same tick)
console.log(diff())
setTimeout(function () {
// second invocation returns new diff since start, so we'll see 100
console.log(diff())
}, 100)
In case you need nanosecond precision, please use https://github.com/sindresorhus/time-span.
NANOBENCH version 2
> /Users/marcbachmann/.nvm/versions/node/v8.1.2/bin/node bench.js
# 10 million operations using Date.now
ok ~1.74 s (1 s + 740748587 ns)
# 10 million using wrapped process.hrtime
ok ~1.99 s (1 s + 985111399 ns)
# 10 million operations directly using process.hrtime, without conversion
ok ~1.54 s (1 s + 540457122 ns)
all benchmarks completed
ok ~5.27 s (5 s + 266317108 ns)