Total memory used by Python process?

Question

Is there a way for a Python program to determine how much memory it\'s currently using? I\'ve seen discussions about memory usage for a single object, but what I need is tot

Answer 1

Even easier to use than /proc/self/status: /proc/self/statm. It's just a space delimited list of several statistics. I haven't been able to tell if both files are always present.

/proc/[pid]/statm

Provides information about memory usage, measured in pages. The columns are:

• size (1) total program size (same as VmSize in /proc/[pid]/status)
• resident (2) resident set size (same as VmRSS in /proc/[pid]/status)
• shared (3) number of resident shared pages (i.e., backed by a file) (same as RssFile+RssShmem in /proc/[pid]/status)
• text (4) text (code)
• lib (5) library (unused since Linux 2.6; always 0)
• data (6) data + stack
• dt (7) dirty pages (unused since Linux 2.6; always 0)

Here's a simple example:

from pathlib import Path
from resource import getpagesize

PAGESIZE = getpagesize()
PATH = Path('/proc/self/statm')


def get_resident_set_size() -> int:
    """Return the current resident set size in bytes."""
    # statm columns are: size resident shared text lib data dt
    statm = PATH.read_text()
    fields = statm.split()
    return int(fields[1]) * PAGESIZE


data = []
start_memory = get_resident_set_size()
for _ in range(10):
    data.append('X' * 100000)
    print(get_resident_set_size() - start_memory)

That produces a list that looks something like this:

0
0
368640
368640
368640
638976
638976
909312
909312
909312

You can see that it jumps by about 300,000 bytes after roughly 3 allocations of 100,000 bytes.