comparision

comp.py

# for normal file
import os
import time
start_time = time.time()
with open("example_file.pdf","rb") as f:
    buffer_size = 64
    retract_size = -32
    while True:
        f.seek(buffer_size,os.SEEK_CUR)
        pass
        f.seek(retract_size,os.SEEK_CUR)
        pass
        if f.tell() >  15728640: # 15MB
            break
end_time = time.time()
print(end_time - start_time) --> 2.992995500564575

# for memory mapped file
import os
import time
import mmap
start_time = time.time()
with open("example_file.pdf","rb") as f:
    with mmap.mmap(f.fileno(),0,access=mmap.ACCESS_READ) as m:
        buffer_size = 64
        retract_size = -32
        while True:
            m.seek(buffer_size,os.SEEK_CUR)
            pass
            m.seek(retract_size,os.SEEK_CUR)
            pass
            if m.tell() > 15728640: # 15MB
                break
end_time = time.time()
print(end_time - start_time) --> 0.23140549659729004