How to Use Linux Server Kernel Same-page Merging for Memory Optimization

Linux Server Admin with Fexingo: Sysadmin, Bash, and Server Engineering · Jul 5, 2026 · 8m · transcript

Kernel Same-page Merging (KSM) is a Linux kernel feature that deduplicates identical memory pages across processes, dramatically reducing RAM usage in virtualized and containerized environments. In this episode, Lucas and Luna dive into how KSM works under the hood, when to enable it, and real-world performance trade-offs. They walk through enabling KSM on a Debian 12 server, tuning merge_across_nodes and full_scans parameters, and measuring memory savings with ksmctl and /sys/kernel/mm/ksm. They also discuss security considerations—side-channel attacks like Rowhammer—and why KSM is a mixed…