Down: Debunking zswap and zram myths

Chris Down has posted adetailed look at how the kernel's zswap and zram subsystems work - andhow they differ.

Most people think of zswap and zram simply as two differentflavours of the same thing: compressed swap. At a surface level,that's correct - both compress pages that would otherwise end up ondisk - but they make fundamentally different bets about how thekernel should handle memory pressure, and picking the wrong one foryour situation can actively make things worse than having no swapat all