Documentation for /proc/sys/vm/ in the Linux kernel documentation

Primary Linux v6.12 documentation, compact_memory and compaction_proactiveness sections: compaction seeks contiguous free physical blocks where possible, and moving pages can impose latency and execution costs. The cited URL pins the documentation set; the page also retains a historical introductory version note. This source is used for the compaction sections, not as a claim about every current system default.