The Datadog team discovered a bug in their agent that caused it to hang indefinitely on systems with certain types of network file systems, specifically NFS. The issue was traced to the `os.statvfs` function, which is a Linux system call that can cause the system to hang if used in an unkillable state. This happens when trying to stat a remote directory mounted with NFS, and it's a known issue due to the way NFS handles connections. To fix this, the Datadog team had to implement a workaround by running the `statvfs` call on a separate thread and using a timeout to prevent the main thread from hanging. This solution comes with trade-offs, such as slightly increased memory usage on systems with hard-mounted NFS disks, but it allows the agent to operate in a wide range of heterogeneous environments.