Post Syndicated from corbet original https://lwn.net/Articles/1064478/

Chris Down has posted a
detailed look at how the kernel’s zswap and zram subsystems work — and
how they differ.

Most people think of zswap and zram simply as two different
flavours of the same thing: compressed swap. At a surface level,
that’s correct – both compress pages that would otherwise end up on
disk – but they make fundamentally different bets about how the
kernel should handle memory pressure, and picking the wrong one for
your situation can actively make things worse than having no swap
at all