* fix(tikv): replace DeleteRange with transaction-based batch deletes
Fixes#7187
Problem:
TiKV's DeleteRange API is a RawKV operation that bypasses transaction
isolation. When SeaweedFS filer uses TiKV with txn client and another
service uses RawKV client on the same cluster, DeleteFolderChildren
can accidentally delete KV pairs from the RawKV client because
DeleteRange operates at the raw key level without respecting
transaction boundaries.
Reproduction:
1. SeaweedFS filer using TiKV txn client for metadata
2. Another service using rawkv client on same TiKV cluster
3. Filer performs batch file deletion via DeleteFolderChildren
4. Result: ~50% of rawkv client's KV pairs get deleted
Solution:
Replace client.DeleteRange() (RawKV API) with transactional batch
deletes using txn.Delete() within transactions. This ensures:
- Transaction isolation - operations respect TiKV's MVCC boundaries
- Keyspace separation - txn client and RawKV client stay isolated
- Proper key handling - keys are copied to avoid iterator reuse issues
- Batch processing - deletes batched (10K default) to manage memory
Changes:
1. Core data structure:
- Removed deleteRangeConcurrency field
- Added batchCommitSize field (configurable, default 10000)
2. DeleteFolderChildren rewrite:
- Replaced DeleteRange with iterative batch deletes
- Added proper transaction lifecycle management
- Implemented key copying to avoid iterator buffer reuse
- Added batching to prevent memory exhaustion
3. New deleteBatch helper:
- Handles transaction creation and lifecycle
- Batches deletes within single transaction
- Properly commits/rolls back based on context
4. Context propagation:
- Updated RunInTxn to accept context parameter
- All RunInTxn call sites now pass context
- Enables proper timeout/cancellation handling
5. Configuration:
- Removed deleterange_concurrency setting
- Added batchdelete_count setting (default 10000)
All critical review comments from PR #7188 have been addressed:
- Proper key copying with append([]byte(nil), key...)
- Conditional transaction rollback based on inContext flag
- Context propagation for commits
- Proper transaction lifecycle management
- Configurable batch size
Co-authored-by: giftz <giftz@users.noreply.github.com>
* fix: remove extra closing brace causing syntax error in tikv_store.go
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Co-authored-by: giftz <giftz@users.noreply.github.com>
Chris Lu
5287d9f3e3