Hi Liu Han, Thanks for driving this proposal. I've reviewed FIP-33 and the overall design looks good to me (LGTM).
Looking forward to the vote and follow-up phases. Best, Jark On Wed, 25 Mar 2026 at 22:55, liu han <[email protected]> wrote: > > liu han <[email protected]> > 5:08 PM (5 hours ago) > to dev > Hi devs, > > I'd like to start a discussion about FIP-33: JBOD Phase 1 - Local > Multi-Directory Support [1]. > > Fluss currently assumes a single `data.dir` on each TabletServer. This > works for single-disk deployments, but it does not make good use of servers > with multiple local disks, where we would like to better utilize available > disk capacity and I/O bandwidth. > > To support JBOD incrementally and keep the design low-risk, we plan to > introduce it in three phases: > > 1. Phase 1: Local Multi-Directory Support > 2. Phase 2: Single-Disk Failure Isolation > 3. Phase 3: Inter-Disk Data Rebalancing > > This FIP focuses on Phase 1 only. > > The goal of Phase 1 is to enable multiple local data directories on > TabletServer, support static bucket placement across directories, recover > bucket placement after restart, and keep `log + kv` co-located for primary > key tables, while remaining compatible with the existing single-directory > deployment model. > > This phase does not introduce metadata, RPC, protobuf, or coordinator > changes. It also does not cover disk failure isolation or inter-disk > migration, which are planned for later phases. > > Any feedback and suggestions are welcome! > > [1] > https://cwiki.apache.org/confluence/display/FLUSS/FIP-33%3A+JBOD+Phase+1+-+Local+Multi-Directory+Support
