$ cat foo.go
package main

import "fmt"

func main() {
    fmt.Println()
}

$ for i in {1..10}; do time godef -i -o 52 <foo.go >/dev/null; done 
godef -i -o 52 < foo.go > /dev/null  0.02s user 0.00s system 98% cpu 0.021 total
godef -i -o 52 < foo.go > /dev/null  0.02s user 0.00s system 99% cpu 0.019 total
godef -i -o 52 < foo.go > /dev/null  0.02s user 0.00s system 99% cpu 0.018 total
godef -i -o 52 < foo.go > /dev/null  0.02s user 0.00s system 91% cpu 0.023 total
godef -i -o 52 < foo.go > /dev/null  0.01s user 0.00s system 100% cpu 0.017 total
godef -i -o 52 < foo.go > /dev/null  0.01s user 0.00s system 100% cpu 0.016 total
godef -i -o 52 < foo.go > /dev/null  0.01s user 0.00s system 99% cpu 0.015 total
godef -i -o 52 < foo.go > /dev/null  0.01s user 0.00s system 99% cpu 0.014 total
godef -i -o 52 < foo.go > /dev/null  0.01s user 0.00s system 97% cpu 0.013 total
godef -i -o 52 < foo.go > /dev/null  0.02s user 0.00s system 99% cpu 0.019 total

$ for i in {1..10}; do time guru describe foo.go:\#52 >/dev/null; done
guru describe foo.go:\#52 > /dev/null  0.77s user 0.04s system 440% cpu 0.183 total
guru describe foo.go:\#52 > /dev/null  0.56s user 0.04s system 372% cpu 0.162 total
guru describe foo.go:\#52 > /dev/null  0.58s user 0.02s system 430% cpu 0.140 total
guru describe foo.go:\#52 > /dev/null  0.61s user 0.03s system 443% cpu 0.144 total
guru describe foo.go:\#52 > /dev/null  0.56s user 0.03s system 444% cpu 0.133 total
guru describe foo.go:\#52 > /dev/null  0.61s user 0.03s system 450% cpu 0.143 total
guru describe foo.go:\#52 > /dev/null  0.57s user 0.03s system 431% cpu 0.138 total
guru describe foo.go:\#52 > /dev/null  0.66s user 0.03s system 460% cpu 0.152 total
guru describe foo.go:\#52 > /dev/null  0.56s user 0.04s system 389% cpu 0.154 total
guru describe foo.go:\#52 > /dev/null  0.56s user 0.03s system 447% cpu 0.132 total