asdf.rb

#Add before any other code in `bin/brew`

module Kernel
  alias_method :old_backtick, :`
  alias_method :old_system, :system
  def system *args
    t = Time.now
    old_system *args
    puts "#{Time.now - t}: #{args*' '}"
  end
  def ` arg
    t = Time.now
    s = old_backtick arg
    puts "#{Time.now - t}: `#{arg}`"
    s
  end
end

gistfile1.sh

$ time brew audit android-ndk amap alure aldo
0.027497: `/usr/bin/sw_vers -productVersion`
0.011199: `/usr/bin/which brew-audit 2>/dev/null`
0.005405: `/usr/bin/which brew-audit.rb`
0.013156: `xcode-select -print-path 2>/dev/null`
0.28202: `/Applications/Xcode.app/Contents/Developer/usr/bin/xcodebuild -version 2>/dev/null`
0.739916: `/usr/bin/xcodebuild -version -sdk macosx10.8 Path 2>/dev/null`
0.005013: `/usr/sbin/sysctl -n hw.ncpu`
0.011435: `xcode-select -print-path 2>/dev/null`
0.016608: `/usr/bin/xcrun -find llvm-gcc 2>/dev/null`
0.01528: `/usr/bin/xcrun -find make 2>/dev/null`
0.012752: `/usr/bin/xcrun -find make`
0.011144: `/Applications/Xcode.app/Contents/Developer/usr/bin/llvm-gcc --version`

real	0m1.146s
user	0m0.908s
sys	0m0.247s

$ time brew audit android-ndk amap alure aldo

real    0m11.708s
user    0m2.591s
sys 0m0.833s
[~/homebrew] (master)