Unnecessary ZFS Overhead
When you install Ubuntu using the experimental ZFS on root filesystem option, the operating system installs a background service called zsysd (ZFS System Daemon). This daemon is responsible for tracking system states and automatically taking ZFS snapshots of your entire filesystem right before you install packages (using apt) or apply system updates. This allows you to easily roll back the entire OS if an update breaks something.
While this is an incredibly powerful feature for desktop users testing unstable software, it can cause significant performance hiccups on busy servers. The automatic snapshotting process can briefly pause I/O operations, leading to latency spikes during automated package deployments. If you manually manage your ZFS snapshots, rely on dedicated backup solutions, or simply want to stop the background daemon from interfering with apt, you can disable zsysd.
How to Disable the Zsysd Daemon
You can stop and disable the daemon using standard systemd commands.
- Open your Ubuntu Terminal or connect via SSH.
- Stop the currently running service:
sudo systemctl stop zsysd.service- Disable the service to prevent it from starting on the next boot:
sudo systemctl disable zsysd.service- Because apt triggers zsys via a pre-invoke hook, you should also remove or comment out the apt integration to prevent warnings when installing packages:
sudo rm /etc/apt/apt.conf.d/90_zsys_system_autosnapshotYour system will no longer automatically generate ZFS snapshots during software installations, allowing apt to run faster and without I/O interruptions.