Device Mapper is the invisible engine under your LVM volumes, your dm-crypt containers, your thin pools, and your multipath setup.

You quite likely use it every day. But do you know it?

This is the one where we open the bonnet: we'll cover dmsetup power moves — the low-level commands that let you inspect, manipulate, and sometimes terrify your storage stack in ways the higher-level tools don't expose.

We'll dive into dmstats, the criminally underused performance measurement framework that lets you track I/O at per-region, per-object granularity and actually answer the question "where is my storage bottleneck?" And we'll look at dmpy, a Python automation library that lets you drive all of this programmatically without shelling out to dmsetup like it's 2003.

The workshop will provide practical, useful, hands-on exercises that users can try out right away using provided VM images/KS files.

No prerequisites beyond basic system admin skills.

Within openSUSE, transactional systems, based on btrfs snapshotting are offered, through the MicroOS product.

Transactional systems offer a middle ground between Fedora Atomics, and their image based updating, and read-only filesystems and Traditional Fedora, with it's read/write filesystems, as they can be configured to do either, offering great flexibility.

In a read-only context, transactional Fedora offers a minimal system, and workloads are handled through podman or docker containers, for server usage. On the desktop, toolbox, distrobox, flatpaks, and potentially other application delivery mechanisms can be used, while still providing the possibility of local modifications to the read-only filesystem, for things that just make sense to be delivered via RPM.

In a read-write context, Transactional systems offer Atomic updating, offering the possibility of more reliable updating, more stable systems over time, and the ability to "rollback" snapshots, in case of issues. or for troubleshooting purposes.

This talk will discuss the basic ideas behind Transactional Updates, how they're used in openSUSE, and what it takes to bring them to Fedora.