config ZCACHE2 bool "Dynamic compression of swap pages and clean pagecache pages" depends on CRYPTO=y && SWAP=y && CLEANCACHE && FRONTSWAP && !ZCACHE select CRYPTO_LZO default n help Zcache2 doubles RAM efficiency while providing a significant performance boosts on many workloads. Zcache2 uses compression and an in-kernel implementation of transcendent memory to store clean page cache pages and swap in RAM, providing a noticeable reduction in disk I/O. Zcache2 is a complete rewrite of the older zcache; it was intended to be a merge but that has been blocked due to political and technical disagreements. It is intended that they will merge again in the future. Until then, zcache2 is a single-node version of ramster. config RAMSTER bool "Cross-machine RAM capacity sharing, aka peer-to-peer tmem" depends on CONFIGFS_FS=y && SYSFS=y && !HIGHMEM && ZCACHE2=y depends on NET # must ensure struct page is 8-byte aligned select HAVE_ALIGNED_STRUCT_PAGE if !64_BIT default n help RAMster allows RAM on other machines in a cluster to be utilized dynamically and symmetrically instead of swapping to a local swap disk, thus improving performance on memory-constrained workloads while minimizing total RAM across the cluster. RAMster, like zcache2, compresses swap pages into local RAM, but then remotifies the compressed pages to another node in the RAMster cluster.