Adding the ability to read from a parent WAL and write to a new WAL - #6
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before cloning, `copy_wal_ssts` would fail with `NotFound` trying to copy WAL SSTs that no longer exist (but whose data is safely in L0). `copy_wal_ssts` now skips `NotFound` WAL SSTs at the start of the copy range (these are WALs already flushed to L0) and returns an adjusted `replay_after_wal_id` so the clone manifest doesn't reference them. Missing WALs after a successfully copied WAL still error, since that indicates actual data loss rather than post-flush cleanup.
…ed-up WAL files When a DB opens, fence_writers writes an empty WAL SST that advances next_wal_sst_id but not replay_after_wal_id, leaving a gap of 1. After a full flush the memtable is empty, so flush_memtables never freezes or flushes anything, and replay_after_wal_id stays behind. If the WAL store is later cleaned up externally (e.g. local disk wiped after a shard split), a clone created from this checkpoint tries to copy the missing fencing WAL and crashes with NotFound. Fix: after CheckpointScope::All flushes complete, advance replay_after_wal_id to next_wal_sst_id - 1. All data is already in L0 at that point, so the remaining WAL SSTs are redundant.
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Adding the ability to read from a parent WAL and write to a new WAL
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Adding the ability to read from a parent WAL and write to a new WAL
Adding the ability to read from a parent WAL and write to a new WAL
Summary
What is being changed and why?
Changes
Notes for Reviewers
Any hints on how to best review this PR? Anything you’d like reviewers to focus on? Any follow-ups planned?
Checklist
cargo fmt,cargo clippy --all-targets --all-features, andcargo nextest run --all-featuresThank you for the review! 🙏