get maximum docker containers memory usage

monitor_docker_ram_usage.py

import subprocess

from decimal import Decimal


class DockerStatsParser():

    def __init__(self):
        self.max_memory = 0

    def get_docker_stats(self):
        process = subprocess.run(
            ["docker stats --no-stream --format '{{.MemUsage}}'"], 
            shell=True, 
            check=True, 
            stdout=subprocess.PIPE, 
            universal_newlines=True
        )
        return process.stdout

    def get_GiB_from_memory_string(self, str):
        if "GiB" in str:
            return Decimal(str.replace("GiB", "").strip())
        if "MiB" in str:
            return Decimal(str.replace("MiB", "").strip()) / Decimal("1024")

    def get_total_memory(self, stats_output):
        total_memory = Decimal(0)
        stats_lines = stats_output.splitlines()
        for line in stats_lines:
            memory_str = line.split("/")[0]
            memory_GiB = self.get_GiB_from_memory_string(memory_str)
            total_memory += memory_GiB
        return total_memory

    def run(self):
        while True:
            stats = self.get_docker_stats()
            total_memory = self.get_total_memory(stats)
            if total_memory > self.max_memory:
                self.max_memory = total_memory
            print(f"current: {total_memory} \t max: {self.max_memory}")

if __name__ == "__main__":
    stats = DockerStatsParser()
    stats.run()