Hi,
Yep, it's a good question. Btrfs is slower on some things and faster on others.
It's tedious to do good benchmarking, not least of which is synthetic benchmarks are
only helpful if they truly approximate your workload.
One of the optional features being considered in the proposal is compression for select
directories. This reduces the amount of reads and writes, which reduces latencies, and can
sometimes improve performance. It'll also increase flash lifespan due to less write
amplification.
The main goal is to make sure most folks don't notice the change, and don't have
to learn a bunch of new commands or start doing strange rituals to hand hold the file
system. And not expect people to become file system experts to benefit from some useful
features.
--
Chris Murphy