lrzip

What lrzip is

lrzip is a command-line compression utility for large files, usually those over 10–50 MB. It first reduces redundancy between distant parts of a file using an extended form of rzip, then applies a compression backend such as LZMA, ZPAQ, LZO, GZIP, or BZIP2. It can also leave data uncompressed after the first pass. The project says users can optimize for speed or output size, but not both at once. Compression and decompression use multiple threads, with CPU count detected automatically. lrzip uses available RAM for its compression windows; a sliding mmap mode allows windows larger than RAM but can be extremely slow. Encryption is available, and the default option uses AES-256-GCM with PBKDF2-HMAC-SHA512 and HKDF. Forgotten encryption passwords cannot be recovered. The main program handles single files, while the lrztar wrapper can package directories. It is free, GPL-2.0 licensed software for 64-bit Unix-like systems, including macOS 10.5 or later with version 0.43 and later. Compression needs substantial memory and a modern processor for best performance.