Tracking *maximum* memory usage by a Python function

Question

I want to find out what the maximum amount of RAM allocated during the call to a function is (in Python). There are other questions on SO related to tracking RAM usage:

Answer 1

Reading the source of free's information, /proc/meminfo on a linux system:

~ head /proc/meminfo
MemTotal:        4039168 kB
MemFree:         2567392 kB
MemAvailable:    3169436 kB
Buffers:           81756 kB
Cached:           712808 kB
SwapCached:            0 kB
Active:           835276 kB
Inactive:         457436 kB
Active(anon):     499080 kB
Inactive(anon):    17968 kB

I have created a decorator class to measure memory consumption of a function.

class memoryit:

    def FreeMemory():
        with open('/proc/meminfo') as file:
            for line in file:
                if 'MemFree' in line:
                    free_memKB = line.split()[1]
                    return (float(free_memKB)/(1024*1024))    # returns GBytes float

    def __init__(self, function):    # Decorator class to print the memory consumption of a 
        self.function = function     # function/method after calling it a number of iterations

    def __call__(self, *args, iterations = 1, **kwargs):
        before = memoryit.FreeMemory()
        for i in range (iterations):
            result = self.function(*args, **kwargs)
        after = memoryit.FreeMemory()
        print ('%r memory used: %2.3f GB' % (self.function.__name__, (before - after) / iterations))
        return result

Function to measure consumption:

@memoryit
def MakeMatrix (dim):
    matrix = []   
    for i in range (dim):
        matrix.append([j for j in range (dim)])
    return (matrix)

Usage:

print ("Starting memory:", memoryit.FreeMemory()) 
m = MakeMatrix(10000)    
print ("Ending memory:", memoryit.FreeMemory() )

Printout:

Starting memory: 10.58599853515625
'MakeMatrix' memory used: 3.741 GB
Ending memory: 6.864116668701172