shai@lappy ~ % time ruby fog-example.rb
1058
ruby fog-example.rb 3.66s user 0.21s system 20% cpu 18.895 total
shai@lappy ~ % time ruby fog-example-cache.rb
could not find cache. loading from api.
ruby fog-example-cache.rb 5.58s user 0.35s system 29% cpu 20.423 total
shai@lappy ~ % time ruby fog-example-cache.rb
found cache.
1058
ruby fog-example-cache.rb 3.11s user 0.17s system 80% cpu 4.087 total
An increase of about ~500% in speed, from 20 secs to 4 secs on an account with ~1k instances being fetched from the api.