kabo87777 opened a new pull request, #16735:
URL: https://github.com/apache/iotdb/pull/16735
# Fix Non-Deterministic Behavior in
InnerUnseqCompactionWithReadPointPerformerTest
## Problem
`InnerUnseqCompactionWithReadPointPerformerTest.test` was failing
non-deterministically under NonDex with 100% failure rate (10/10 runs) due to
reliance on HashMap/HashSet iteration order in test setup and file generation.
## Way to Reproduce
```bash
cd iotdb-core/datanode
mvn edu.illinois:nondex-maven-plugin:2.1.1:nondex \
-Dtest=InnerUnseqCompactionWithReadPointPerformerTest#test \
-DnondexRuns=10 -Drat.skip=true
# Result: 10/10 failures with varying expected/actual values
# Example: expected:<1149> but was:<2949>
```
## Root Cause
Multiple HashMap/HashSet usages caused non-deterministic iteration order:
1. **Test expectations map** (`chunkPagePointsNumMerged`): HashMap iteration
affected assertion order
2. **Measurement paths set** (`fullPath`): HashSet iteration determined
TsFile write order
3. **Modification maps** (`toDeleteTimeseriesAndTime`): HashMap affected
deletion ordering
4. **Device-measurement grouping** in `CompactionFileGeneratorUtils`:
HashMap caused non-deterministic device ordering in generated TsFiles
When NonDex shuffled collection order, measurements/devices were written in
different sequences, causing expected chunk/page point counts to mismatch
actual values.
## Solution
**InnerUnseqCompactionWithReadPointPerformerTest.java:**
- Changed `Set<String> fullPath` from HashSet to LinkedHashSet (line 130)
- Changed `toDeleteTimeseriesAndTime` maps from HashMap to LinkedHashMap
(lines 313, 356)
- Changed `chunkPagePointsNumMerged` from HashMap to LinkedHashMap (line 383)
**CompactionFileGeneratorUtils.java:**
- Changed `deviceMeasurementMap` from HashMap to LinkedHashMap in
`writeChunkToTsFileWithTimeRange()` method
## Verification
```bash
cd iotdb-core/datanode
mvn edu.illinois:nondex-maven-plugin:2.1.1:nondex \
-Dtest=InnerUnseqCompactionWithReadPointPerformerTest#test \
-DnondexRuns=20 -Drat.skip=true
# Result: 20/20 passes (100% success rate)
```
---
**Key changed classes:**
- `InnerUnseqCompactionWithReadPointPerformerTest` (test changes only)
- `CompactionFileGeneratorUtils` (test utility changes only)
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