Kerncompressor

Kerncompressor is a software tool designed to compress kernel images and related boot-time data using lossless compression. It provides a workflow for packaging a kernel and its initramfs in a compressed form to reduce on-disk size and memory footprint during boot, while preserving binary compatibility with the kernel's decompression code.

The project supports multiple compression algorithms, including zstd, LZMA, and deflate variants, and offers a kernel-aware layout that places a small decompression stub alongside metadata such as a manifest, checksums, and architecture flags. It is designed to work with common bootloaders and can emit images that boot directly in U-Boot, coreboot, or GRUB environments.

Kerncompressor is designed with a modular architecture. The core provides a plugin interface for different compressors, a verifier for integrity checks, and tools to generate and verify a packaging manifest. A small decompressor module or static kernel code is included to perform runtime decompression.

Usage typically involves selecting a compression format, running the tool on a kernel image (and optional initramfs), and distributing the resulting package with a bootloader configuration. The output consists of a compressed kernel image, a bootable header, and a verification manifest.

In development and academic contexts, kerncompressor has been explored as a means to reduce boot times on embedded systems and machines with limited storage. Support and robustness depend on the chosen algorithms and bootloader compatibility, and projects may assess trade-offs between compression ratio, decompression latency, and code size.

See also: Kernel image, Bootloader, Data compression algorithms, Initramfs.