[SPARK-56400][SS] Apply rangeScan API in transformWithState Timer/TTL#55265
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HeartSaVioR wants to merge 9 commits intoapache:masterfrom
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[SPARK-56400][SS] Apply rangeScan API in transformWithState Timer/TTL#55265HeartSaVioR wants to merge 9 commits intoapache:masterfrom
HeartSaVioR wants to merge 9 commits intoapache:masterfrom
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Use bounded scan ranges in transformWithState TTL eviction and timer expiry to narrow the iteration scope: - TTLState.ttlEvictionIterator: use store.scan with startKey from prevBatchTimestampMs+1 and endKey from batchTimestampMs+1 to skip entries already cleaned up in the previous batch. - TimerStateImpl.getExpiredTimers: use store.scan with startKey from prevExpiryTimestampMs+1 and endKey from expiryTimestampMs+1. Processing-time timers use prevBatchTimestampMs; event-time timers use eventTimeWatermarkForLateEvents. Thread prevBatchTimestampMs from IncrementalExecution (via prevOffsetSeqMetadata) through TransformWithStateExec -> StatefulProcessorHandleImpl -> TTLState / TimerStateImpl. Copy UnsafeRow results from encodeTTLRow/UnsafeProjection to avoid the mutable-row-reuse bug where startKey and endKey alias the same internal buffer.
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Only the last commit is related to this PR. Once #55226 is merged, I'll rebase. |
bogao007
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Apr 10, 2026
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Got some questions but LGTM overall!
| // The schema of the UnsafeRow returned by this iterator is (expirationMs, elementKey). | ||
| private[sql] def ttlEvictionIterator(): Iterator[UnsafeRow] = { | ||
| val ttlIterator = store.iterator(TTL_INDEX) | ||
| val dummyElementKey = ELEMENT_KEY_PROJECTION |
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Is the dummyElementKey here just for using TTL_ENCODER.encodeTTLRow requires an elementKey?
| } else { | ||
| None | ||
| } | ||
| val ttlIterator = store.rangeScan(startKey, endKey, TTL_INDEX) |
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Should we update the method comment indicating that we are using range scan now?
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What changes were proposed in this pull request?
This PR proposes to apply rangeScan API in transformWithState Timer/TTL, which will give an improvement of scanning on expired timers and entries with configured TTL.
The main idea is to perform scanning of expired timers and TTL entries from [the end timestamp of previous scan + 1, new end timestamp], which was [None, new end timestamp]. Previously it had to go through tombstones prior batches made in prior evictions (till compaction happens), and with this change we will be able to skip those tombstones.
Why are the changes needed?
This change will give a hit to RocksDB about the exact range to scan, reducing the chance of reading tombstone a lot.
Does this PR introduce any user-facing change?
No.
How was this patch tested?
New UTs, and existing UTs.
Was this patch authored or co-authored using generative AI tooling?
Generated-by: Claude 4.6 Opus