Every a9s Data Service service instance has an a9s Parachute process running. This process will stop the
node process when the persistent disk hits
80% of usage. This is valid for all services.
The persistent disk is mounted using ext4, this file system reserves a portion of the filesystem
(5% by default) for the root user to prevent, among other things, normal users (
filling the disk and crashing the system.
The calculation for the used disk space does not consider the reserved disk space, and it is calculated over the overall disk usage.