How to Reduce the time taken to load a pickle file in python

Question

I have created a dictionary in python and dumped into pickle. Its size went to 300MB. Now, I want to load the same pickle.

output = open(\'myfile.pkl\', \'rb         


        

Answer 1

I've had nice results in reading huge files (e.g: ~750 MB igraph object - a binary pickle file) using cPickle itself. This was achieved by simply wrapping up the pickle load call as mentioned here

Example snippet in your case would be something like:

import timeit
import cPickle as pickle
import gc


def load_cpickle_gc():
    output = open('myfile3.pkl', 'rb')

    # disable garbage collector
    gc.disable()

    mydict = pickle.load(output)

    # enable garbage collector again
    gc.enable()
    output.close()


if __name__ == '__main__':
    print "cPickle load (with gc workaround): "
    t = timeit.Timer(stmt="pickle_wr.load_cpickle_gc()", setup="import pickle_wr")
    print t.timeit(1),'\n'

Surely, there might be more apt ways to get the task done, however, this workaround does reduce the time required drastically. (For me, it reduced from 843.04s to 41.28s, around 20x)