Reproducing WALinuxAgent Memory Leak

Create Azure VM

In Azure Portal, create a virtual machine using Ubuntu Server 18.04 LTS image. I used West US on Standard B1ms (1 cpu, 2GiB memory). Add SSH credentials and user name and set up networking as appropriate.

On the Advanced tab, click select an extension to install and then select Custom Script for Linux. Click create. On the Install extension page, copy/paste the dummy command from command-to-execute.txt in this repo into Command field. Click OK.

Finish creating the VM as typical.

Set Up Ansible

Replace the IP address in hosts file with the IP address of the new VM. Set up the ansible.cfg with the remote_user and private_key_file associated with the new VM.

Run Ansible

You will require a key to access the repository that contains Bayware ib-agent.

]$ ansible-playbook -e repo_key_id="<from-Bayware>" -e repo_secret_key="<from-Bayware>" start-leak.yml

Check VM Memory

Log into your VM, switch to root, and run htop. When viewed as a tree, subprocesses under /usr/bin/python3 -u /usr/sbin/waagent -daemon show leak. (That is, processes with WALinuxAgent in the command name.) Memory leak is evident within a couple minutes as usage slowly climbs over 2% (say, at 5% within 30 minutes elapsed time).

Version Information

root@ms-extension5:~# waagent version
WALinuxAgent-2.2.40 running on ubuntu 18.04
Python: 3.6.8
Goal state agent: 2.2.41
root@ms-extension5:~# openssl version
OpenSSL 1.1.1  11 Sep 2018