All of our services run on Docker containers, which are a way to package and run software in a isolated and lightweight environment. Unfortunately, the Docker engine crashed with an exception, causing all services to be stopped. After investigating the issue, we suspect the root cause to be an out-of-memory issue. In order to prevent this from happening again, we have tweaked some server settings and reallocated RAM from file system cache to Docker.
We apologize for any inconvenience this may have caused and are committed to ensuring the stability of our services. Thank you for your patience and understanding.