1. Timing Functions
When optimizing code, sometimes a quick and dirty time measurement is required as opposed to utilizing profiler tools/frameworks to validate assumptions.
Time measurements can be performed by utilizing time
package and defer
statements.
1.1. Implementation
package profile
import (
"time"
"log"
)
func Duration(invocation time.Time, name string) {
elapsed := time.Since(invocation)
log.Printf("%s lasted %s", name, elapsed)
}
1.2. Usage
func BigIntFactorial(x big.Int) *big.Int {
// Arguments to a defer statement is immediately evaluated and stored.
// The deferred function receives the pre-evaluated values when its invoked.
defer profile.Duration(time.Now(), "IntFactorial")
y := big.NewInt(1)
for one := big.NewInt(1); x.Sign() > 0; x.Sub(x, one) {
y.Mul(y, x)
}
return x.Set(y)
}