JSON vs cPickle in Python 2.7

gistfile1.py

#!/usr/bin/env python

# Average runs looks like this:
# $ ./serialization.py 
# Starting json...
# done: 5.75292301178
# Starting simplejson...
# done: 6.66689586639
# Starting cjson...
# done: 2.09307098389
# Starting pickle...
# done: 6.19903492928

import time
import cPickle as pickle
import simplejson
import json
import cjson

d = {
    'foo': 'bar',
    'food': 'barf',
    'good': 'bars',
    'dood': 'wheres your car?',
    'wheres your car': 'dude?',
}

print 'Starting json...'
start = time.time()
for i in xrange(1000000):
    json.dumps(d)
print 'done:', time.time() - start

print 'Starting simplejson...'
start = time.time()
for i in xrange(1000000):
    simplejson.dumps(d)
print 'done:', time.time() - start

print 'Starting cjson...'
start = time.time()
for i in xrange(1000000):
    cjson.encode(d)
print 'done:', time.time() - start

print 'Starting pickle...'
start = time.time()
for i in xrange(1000000):
    pickle.dumps(d)
print 'done:', time.time() - start