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Home > CentOS > CentOS 6.x > Virtualization tools > Ksm

ksm refers to "Kernel Same-page merging" where similar pages in memory are merged with copy-on-write bit set. The information about KSM at wikipedia page https://en.wikipedia.org/wiki/Kernel_SamePage_Merging_%28KSM%29 highlights its usefulness in case of virtualization. It is always good to have it enabled in cases where optimization of RAM is important than optimization of CPU.