How long should "rake routes" run?

Question

I just started out with Rails, so excuse my fairly basic question. I am already noticing that the rake routes command takes a while to execute everytime I run it. I have about 20 routes for 3 controllers and it takes about 40 seconds to execute.

Is that normal? How could I speed this up?

P.S.: I am on Windows 7 with Rails 3.1.3 (set up with Rails Installer).

Answer 1

The rake routes task depends on the environment task which loads your Rails environment and requires thousands of Ruby files.

The startup time of a Rails environment and the corresponding rake routes execution time are very close (on my Linux on-steroids-laptop with a Rails application with ~ 50 routes):

$ time ruby -r./config/environment.rb -e ''

real    0m5.065s
user    0m4.552s
sys 0m0.456s

$ time rake routes

real    0m4.955s
user    0m4.580s
sys 0m0.344s

There is no easy way to decrease startup time as it relies on the way your interpreter requires script files : http://rhnh.net/2011/05/28/speeding-up-rails-startup-time

Answer 2

I came up with a solution to rake routes taking about 8 seconds to run every time. It's a simple file based cache that runs bundle exec rake routes, stores the output in a file under tmp. The filename is the md5 hash of config/routes.rb, so if you make a change and change it back, it will use the old cached file.

I put the following bash functions in an executable file I call fastroutes:

if [ ! -f config/routes.rb ]; then
  echo "Not in root of rails app"
  exit 1
fi

cached_routes_filename="tmp/cached_routes_$(md5 -q config/routes.rb).txt"

function cache_routes {
  bundle exec rake routes > $cached_routes_filename
}

function clear_cache {
  for old_file in $(ls tmp/cache_routes*.txt); do
    rm $old_file
  done
}

function show_cache {
  cat $cached_routes_filename
}

function show_current_filename {
  echo $cached_routes_filename
}

function main {
  if [ ! -f $cached_routes_filename ]; then
    cache_routes
  fi

  show_cache
}

if [[ "$1" == "-f" ]]
then
  show_current_filename 
elif [[ "$1" == "-r" ]]
then
  rm $cached_routes_filename
  cache_routes
else
  main
fi

Here's a github link too.

This way, you only have to generate the routes once, and then fastroutes will used the cached values.