The Linux Kernel 4.5 was released by Linux Torvalds on Sunday, March 13, 2016.
- copy_file_range(2) system call – This allows files to be copied to a new location without the need to transfer data through the userspace. This makes file copying more efficient, especially for NFS systems.
- Btrfs scalability improvements: All file systems need to keep track of which blocks are free and which are full. Btrfs stores a cache of this information, but it has had problems with systems over 30TB. The new Kernel includes experimental improvements to the btrfs cache that makes it better for large storage devices.
- Support for GCC’s undefined behavior sanitizer – The Kernel can now be compiled to use GCC’s undefined behavior sanitizer. This mechanism checks code at runtime to spot operations that could cause undefined behaviors before they are executed.
- Forward error correction support in device-mapper’s verity target – The device-mapper’s verity target is used on systems that have not been modified to ensure the data has not changed using a list of cryptographic hases. The forward error correction feature makes it possible to recover from a series of small, corrupted blocks.
For a more detailed, beginner-friendly breakdown, check out this article.