CoW (copy-on-write), deduplication of data blocks, replicas (RAID equivalent), file system snapshots and multiple, tiered caching layers, plus several other features.
On a sidenote, I integrated bcachefs as a vmx driver into VMWare ESXi for a CI/CD build server a few years back. The build system ran in VMs and on containers, but the non-essential target directories sat on bcachefs volumes with the caching layer directed first at RAM, then at SSD, then finally at the HDD. Managing all the Unity3D and Unreal caches was amazingly fast across dozens of different SKUs of what the same project.
From my project write-up on my LinkedIn:
Bcache-like caching layer for VMWare ESXi
Reduce latency and read/write delay even if using SSD as your storage.
Written in C and inserting itself as a storage tier into VMWare ESXi to handle read & write storage requests this caching system accelerates all accesses to the underlying backing store.
Can work in both write-back and write-through caching modes. (Native C kernel device driver)
On a sidenote, I integrated bcachefs as a vmx driver into VMWare ESXi for a CI/CD build server a few years back. The build system ran in VMs and on containers, but the non-essential target directories sat on bcachefs volumes with the caching layer directed first at RAM, then at SSD, then finally at the HDD. Managing all the Unity3D and Unreal caches was amazingly fast across dozens of different SKUs of what the same project.
From my project write-up on my LinkedIn: