Uberblok site animates ZFS internals from OpenZFS code
The free educational site walks readers through 14 sections, including a power-loss simulation that shows how ZFS's Copy-on-Write decides which state to load.
Uberblok, a free educational website that explains the internal structure and workings of the ZFS file system through animations and diagrams, has been published. According to Gigazine, the site's animations are built from actual OpenZFS source code, specifically analyzing OpenZFS 2.4.4.
The site is arranged as a museum tour with 14 sections in total. One of them, Room 2, titled "The tree and the uberblock", lets visitors simulate a power loss during a data write and then import the pool to see which state ZFS loads.
That simulation illustrates ZFS's Copy-on-Write mechanism: the updated state is loaded only if the new uberblock was saved before power was cut. Other sections cover checksums and self-healing, RAID-Z, snapshots and clones, and the ARC cache.
Uberblok's source code is released under the MIT license and its text and illustrations under CC BY 4.0, while the OpenZFS code excerpts it uses fall under CDDL 1.0.
Background
ZFS was developed by Sun Microsystems in the 2000s and continues as the open-source OpenZFS project, used in NAS devices and storage servers.
Quick answers
What is Uberblok?
It is a free website that explains ZFS internals through animations and diagrams, organized as a museum tour of 14 sections.
Which OpenZFS version does Uberblok analyze?
The animations are based on OpenZFS source code, specifically OpenZFS 2.4.4.
What licenses does Uberblok use?
Its source code is under the MIT license, text and illustrations under CC BY 4.0, and the OpenZFS code excerpts under CDDL 1.0.