Of the many new features in Linux 4.14, one of the prominent additions is initial support for Zstd compression that is initially wired in for transparent file-system compression with SquashFS and Btrfs. Here are some benchmarks of Zstd Btrfs compression compared to the existing LZO and Zlib compression mount options.

Source: Phoronix – Btrfs Zstd Compression Benchmarks On Linux 4.14