Python MemoryError when trying to load 5GB text file

问题

I want to read data stored in text format in a 5GB file. when I try to read the content of file using this code:

file = open('../data/entries_en.txt', 'r')
data = file.readlines()

an error occurred: data = file.readlines() MemoryError My laptop has 8GB memory and at least 4GB is empty when I want to run the program. but when I monitor the system performance, when python uses about 1.5GB of memory, this error happens.
I'm using python 2.7, but if it matters please tell me solution for 2.x and 3.x What should I do to read this file?

回答1:

The best way for you to handle large files would be -

with open('../file.txt', 'r') as f:
    for line in f:
        # do stuff

readlines() would error because you are trying to load too large a file directly into the memory. The above code will automatically close your file once you are done processing on it.

回答2:

If you want to process lines in the file, you should rather use:

for line in file:
    # do something with the line

It will read the file line by line, instead of reading it all to the RAM at once.

来源：https://stackoverflow.com/questions/26032287/python-memoryerror-when-trying-to-load-5gb-text-file