Python line-by-line memory profiler?

You might be interested by memory_profiler.

I would use sys.settrace at program startup to register a custom tracer function. The custom_trace_function will be called for each line of code. Then you can use that function to store information gathered by heapy or meliae in a file for later processing.

Here is a very simple example which logs the output of hpy.heap() each second to a plain text file:

import sys
import time
import atexit
from guppy import hpy

_last_log_time = time.time()
_logfile = open('logfile.txt', 'w')

def heapy_profile(frame, event, arg):
    currtime = time.time()
    if currtime - _last_log_time < 1:
        return
    _last_log_time = currtime
    code = frame.f_code
    filename = code.co_filename
    lineno = code.co_firstlineno
    idset = hpy().heap()
    logfile.write('%s %s:%s\n%s\n\n' % (currtime, filename, lineno, idset))
    logfile.flush()

atexit.register(_logfile.close)
sys.settrace(heapy_profile)