build: Split ubuntu-debug into separate build and test jobs (facebookincubator#16938)

Summary:
This PR makes two improvements to the Linux CI workflow:

### 1. Split BUILD/TEST status jobs for failure attribution

Split CI job failures into clearly labeled **BUILD** and **TEST** status jobs across all Linux CI workflows, so contributors immediately know what failed from the GitHub Actions UI.

Each job (adapters, ubuntu-debug, fedora-debug) now:
1. Tags build/test steps with `id: build` / `id: tests`
2. Uses `continue-on-error: true` on test steps so the job always completes
3. Exports `build-outcome` and `test-outcome` via job outputs
4. Has lightweight status jobs (`BUILD:` / `TEST:` prefixed) for instant recognition

### 2. Rebalance exec test groups for ~29% faster test execution

The `velox_exec_test` suite uses `velox_add_grouped_tests()` which batches source files positionally into groups of 10. On `main`, the alphabetical ordering creates severely imbalanced groups — the worst group combines IndexLookupJoinTest (971s) + HashTableTest (60s) + MergeJoinTest (111s) = **~1,145s**.

**Changes:**
- **Split IndexLookupJoinTest.cpp** into IndexLookupJoinTest.cpp (~783s) and IndexLookupJoinTestExtra.cpp (~188s) to break up the 971s monolith
- **Split HashJoinTest.cpp** by redistributing 20 MultiThreadedHashJoinTest tests to HashJoinTestExtra.cpp (renamed from HashJoinTestSpill.cpp), balancing ~575s vs ~585s instead of 919s vs 242s
- **Reorder source files** using greedy bin-packing with measured EC2 timings so each group has roughly equal execution time

### Test time improvement

| Metric | main (alphabetical) | This PR (optimized) | Improvement |
|--------|----------------------|---------------------|-------------|
| Slowest group | ~1,145s (19 min) | 817s (13.6 min) | **29% faster** |
| Total wall time (ctest -j24) | ~1,145s | 911s (15.2 min) | **20% faster** |
| Empty groups (wasted parallelism) | 2 groups (~5s each) | 0 | All groups utilized |

**CI-measured group timings (this PR):**

| Group | Anchor Test(s) | CI Time |
|-------|---------------|---------|
| 0 | IndexLookupJoinTest | 745s |
| 1 | MultiFragmentTest | 493s |
| 2 | HashJoinTestExtra | 817s |
| 3 | SpillerTest | 532s |
| 4 | HashJoinTest | 402s |
| 5 | TableWriter + OutputBufMgr + TopNRowNumber + StreamingAgg | 480s |
| 6 | TableScan + Aggregation + OrderBy + HashTable + RowNumber | 556s |
| 7 | IndexLookupJoinExtra + MergeJoin + ScaleWriter + Exchange | 486s |

**100% tests passed (530/530), 0 failures.**

Pull Request resolved: facebookincubator#16938

Test Plan:
- [x] All 8 exec test groups build and link successfully
- [x] All tests pass on EC2 (standalone validation per group)
- [x] CI run validates end-to-end: 530 tests, 0 failures, 911s total
- [x] BUILD/TEST status labels appear correctly in Actions UI
- [x] HashJoinTest split validated: group4 (34 MultiThreaded tests) = 402s, group2 (20 MultiThreaded + 75 HashJoinTest) = 817s
- [x] IndexLookupJoinTest split validated: group0 = 745s, group7 = 486s

Reviewed By: pratikpugalia

Differential Revision: D99000024

Pulled By: kgpai

fbshipit-source-id: 0b503728bb9f3223ed2a9f95f7c5fee69045cdeb

Author: kgpai

.github/workflows/linux-build-base.yml

@@ -94,6 +94,8 @@ jobs:
       USE_CLANG: "${{ inputs.use-clang && 'true' || 'false' }}"
     outputs:
       cudf-changes: ${{ steps.changes.outputs.cudf }}
+      build-outcome: ${{ steps.build.outcome }}
+      test-outcome: ${{ steps.tests.outcome }}
     steps:
       - uses: actions/checkout@v5
         with:
@@ -139,6 +141,7 @@ jobs:
           ccache -sz
 
       - name: Make Release Build
+        id: build
         env:
           MAKEFLAGS: NUM_THREADS=32 MAX_HIGH_MEM_JOBS=12 MAX_LINK_JOBS=12
           CUDA_ARCHITECTURES: 70
@@ -184,6 +187,9 @@ jobs:
           key: ccache-linux-adapters-${{ inputs.use-clang && 'clang' || 'gcc' }}
 
       - name: Run Tests
+        id: tests
+        continue-on-error: true
+        if: steps.build.outcome == 'success'
         env:
           LIBHDFS3_CONF: ${{ github.workspace }}/scripts/ci/hdfs-client.xml
         working-directory: _build/release
@@ -198,7 +204,7 @@ jobs:
       # need to run clang-tidy for that.
       # Let's also run this as last step so that if skipped it doesn't affect subsequent steps.
       - name: Install and run clang-tidy
-        if: ${{ ! inputs.use-clang && needs.get-changes.outputs.run-clang-tidy == 'true' }}
+        if: ${{ steps.build.outcome == 'success' && ! inputs.use-clang && needs.get-changes.outputs.run-clang-tidy == 'true' }}
         env:
           FILES: ${{ needs.get-changes.outputs.changed-files }}
           RANGE: ${{ needs.get-changes.outputs.diff-range }}
@@ -282,6 +288,41 @@ jobs:
             _build/release/velox/experimental/cudf/cudf-libs.tar
           retention-days: ${{ env.RETENTION }}
 
+  adapters-build-status:
+    if: always()
+    needs: adapters
+    runs-on: ubuntu-latest
+    name: "BUILD: Linux adapters release"
+    steps:
+      - run: |
+          if [[ "$BUILD_OUTCOME" != "success" ]]; then
+            echo "Build failed or was cancelled."
+            exit 1
+          fi
+          echo "Build succeeded."
+        env:
+          BUILD_OUTCOME: ${{ needs.adapters.outputs.build-outcome }}
+
+  adapters-test-status:
+    if: always()
+    needs: adapters
+    runs-on: ubuntu-latest
+    name: "TEST: Linux adapters release"
+    steps:
+      - run: |
+          if [[ "$BUILD_OUTCOME" != "success" ]]; then
+            echo "Build failed — tests did not run."
+            exit 1
+          fi
+          if [[ "$TEST_OUTCOME" != "success" ]]; then
+            echo "Tests failed."
+            exit 1
+          fi
+          echo "Tests passed."
+        env:
+          BUILD_OUTCOME: ${{ needs.adapters.outputs.build-outcome }}
+          TEST_OUTCOME: ${{ needs.adapters.outputs.test-outcome }}
+
   cudf-tests:
     runs-on: 4-core-ubuntu-gpu-t4
     needs: adapters
@@ -352,6 +393,9 @@ jobs:
     env:
       CCACHE_DIR: ${{ github.workspace }}/ccache
       USE_CLANG: ${{ inputs.use-clang && 'true' || 'false' }}
+    outputs:
+      build-outcome: ${{ steps.build.outcome }}
+      test-outcome: ${{ steps.tests.outcome }}
     defaults:
       run:
         shell: bash
@@ -401,6 +445,7 @@ jobs:
           ccache -sz
 
       - name: Make Debug Build
+        id: build
         env:
           VELOX_DEPENDENCY_SOURCE: SYSTEM
           ICU_SOURCE: SYSTEM
@@ -430,6 +475,7 @@ jobs:
             EXTRA_CMAKE_FLAGS+=("-DVELOX_ENABLE_FAISS=ON")
             EXTRA_CMAKE_FLAGS+=("-DVELOX_ENABLE_REMOTE_FUNCTIONS=ON")
           fi
+          export EXTRA_CMAKE_FLAGS="${EXTRA_CMAKE_FLAGS[*]}"
           make debug
 
       - name: CCache after
@@ -442,10 +488,48 @@ jobs:
           key: ccache-ubuntu-debug-default-${{ inputs.use-clang && 'clang' || 'gcc' }}
 
       - name: Run Tests
+        id: tests
+        continue-on-error: true
+        if: steps.build.outcome == 'success'
         run: |
           ulimit -n 65536
           cd _build/debug && ctest -j 24 --timeout 1800 --output-on-failure --no-tests=error
 
+  ubuntu-debug-build-status:
+    if: always()
+    needs: ubuntu-debug
+    runs-on: ubuntu-latest
+    name: "BUILD: Ubuntu debug"
+    steps:
+      - run: |
+          if [[ "$BUILD_OUTCOME" != "success" ]]; then
+            echo "Build failed or was cancelled."
+            exit 1
+          fi
+          echo "Build succeeded."
+        env:
+          BUILD_OUTCOME: ${{ needs.ubuntu-debug.outputs.build-outcome }}
+
+  ubuntu-debug-test-status:
+    if: always()
+    needs: ubuntu-debug
+    runs-on: ubuntu-latest
+    name: "TEST: Ubuntu debug"
+    steps:
+      - run: |
+          if [[ "$BUILD_OUTCOME" != "success" ]]; then
+            echo "Build failed — tests did not run."
+            exit 1
+          fi
+          if [[ "$TEST_OUTCOME" != "success" ]]; then
+            echo "Tests failed."
+            exit 1
+          fi
+          echo "Tests passed."
+        env:
+          BUILD_OUTCOME: ${{ needs.ubuntu-debug.outputs.build-outcome }}
+          TEST_OUTCOME: ${{ needs.ubuntu-debug.outputs.test-outcome }}
+
   fedora-debug:
     runs-on: 32-core-ubuntu
     container: ghcr.io/facebookincubator/velox-dev:fedora
@@ -454,6 +538,8 @@ jobs:
     name: Fedora debug
     env:
       CCACHE_DIR: ${{ github.workspace }}/ccache
+    outputs:
+      build-outcome: ${{ steps.build.outcome }}
     defaults:
       run:
         shell: bash
@@ -505,6 +591,7 @@ jobs:
           ccache -sz
 
       - name: Make Debug Build
+        id: build
         env:
           VELOX_DEPENDENCY_SOURCE: SYSTEM
           faiss_SOURCE: BUNDLED
@@ -530,3 +617,18 @@ jobs:
         with:
           path: ${{ env.CCACHE_DIR }}
           key: ccache-fedora-debug-default-gcc
+
+  fedora-debug-build-status:
+    if: always()
+    needs: fedora-debug
+    runs-on: ubuntu-latest
+    name: "BUILD: Fedora debug"
+    steps:
+      - run: |
+          if [[ "$BUILD_OUTCOME" != "success" ]]; then
+            echo "Build failed or was cancelled."
+            exit 1
+          fi
+          echo "Build succeeded."
+        env:
+          BUILD_OUTCOME: ${{ needs.fedora-debug.outputs.build-outcome }}

velox/exec/tests/CMakeLists.txt

@@ -41,87 +41,113 @@ target_link_libraries(
   GTest::gtest_main
 )
 
-# Split velox_exec_test into individual test binaries for parallel execution.
+# Sources are ordered via greedy bin-packing by measured EC2 execution time.
+# With VELOX_TESTS_PER_GROUP=10, CMake takes files positionally in batches of
+# 10 (files 1-10 = group0, 11-20 = group1, etc.).
+#
+# Measured per-file EC2 timings (sequential, 8-core, 30GB):
+#   IndexLookupJoinTest 783s, MultiFragmentTest 599s,
+#   HashJoinTestExtra ~585s, SpillerTest 584s, HashJoinTest ~575s,
+#   TableWriterTest 225s, TableScanTest 189s, IndexLookupJoinTestExtra 188s,
+#   MergeJoinTest 111s, AggregationTest 105s, OutputBufferManagerTest 98s,
+#   ScaleWriterLocalPartitionTest 96s, OrderByTest 71s, TopNRowNumberTest 64s,
+#   HashTableTest 60s, StreamingAggregationTest 58s, ExchangeClientTest 54s,
+#   RowNumberTest 42s.
+#
+# Max group ~784s (bounded by IndexLookupJoinTest.cpp).
 set(
   VELOX_EXEC_TEST_SOURCES
+  # group0 (~784s): IndexLookupJoinTest 783 + 9 lightweight
+  IndexLookupJoinTest.cpp
+  ConcatFilesSpillMergeStreamTest.cpp
+  MixedUnionWithTableScanTest.cpp
+  MemoryReclaimerTest.cpp
+  EnforceDistinctTest.cpp
+  TraceUtilTest.cpp
+  HashPartitionFunctionTest.cpp
+  SpatialIndexTest.cpp
+  ValuesTest.cpp
+  ParallelProjectTest.cpp
+  # group1 (~599s): MultiFragmentTest 599 + 9 lightweight
+  MultiFragmentTest.cpp
+  EnforceSingleRowTest.cpp
+  FilterToExpressionTest.cpp
+  ScaledScanControllerTest.cpp
+  HilbertIndexTest.cpp
+  OperatorTraceTest.cpp
+  LimitTest.cpp
+  SplitListenerTest.cpp
   AddressableNonNullValueListTest.cpp
-  AggregationTest.cpp
-  AggregateFunctionRegistryTest.cpp
   ArrowStreamTest.cpp
-  AssignUniqueIdTest.cpp
-  AsyncConnectorTest.cpp
-  ConcatFilesSpillMergeStreamTest.cpp
-  ContainerRowSerdeTest.cpp
+  # group2 (~585s): HashJoinTestExtra ~585 + 9 lightweight
+  HashJoinTestExtra.cpp
+  AggregateFunctionRegistryTest.cpp
+  RoundRobinPartitionFunctionTest.cpp
   ColumnStatsCollectorTest.cpp
-  CustomJoinTest.cpp
-  EnforceSingleRowTest.cpp
-  ExchangeClientTest.cpp
+  MixedUnionTest.cpp
   ExpandTest.cpp
-  FilterProjectTest.cpp
-  FilterToExpressionTest.cpp
   FunctionResolutionTest.cpp
-  HashBitRangeTest.cpp
-  CountingJoinTest.cpp
-  HashJoinBridgeTest.cpp
-  HashJoinTest.cpp
-  HashPartitionFunctionTest.cpp
-  HashTableTest.cpp
-  IndexLookupJoinTest.cpp
-  LimitTest.cpp
-  LocalPartitionTest.cpp
-  MarkDistinctTest.cpp
+  SpillStatsTest.cpp
   MarkSortedTest.cpp
-  EnforceDistinctTest.cpp
-  MemoryReclaimerTest.cpp
-  MergeJoinTest.cpp
-  MergeTest.cpp
-  MergerTest.cpp
-  MixedUnionTest.cpp
-  MixedUnionWithTableScanTest.cpp
-  MultiFragmentTest.cpp
-  NestedLoopJoinTest.cpp
-  OrderByTest.cpp
-  OperatorTraceTest.cpp
-  OutputBufferManagerTest.cpp
-  ParallelProjectTest.cpp
   PartitionedOutputTest.cpp
-  PlanNodeSerdeTest.cpp
-  PlanNodeStatsTest.cpp
-  PlanNodeToStringTest.cpp
-  PlanNodeToSummaryStringTest.cpp
-  PrefixSortTest.cpp
-  PrintPlanWithStatsTest.cpp
-  ProbeOperatorStateTest.cpp
-  TraceUtilTest.cpp
-  RoundRobinPartitionFunctionTest.cpp
-  RowContainerTest.cpp
-  RowNumberTest.cpp
-  ScaledScanControllerTest.cpp
-  ScaleWriterLocalPartitionTest.cpp
-  SortBufferTest.cpp
-  SpatialIndexTest.cpp
-  HilbertIndexTest.cpp
-  SpillStatsTest.cpp
+  # group3 (~584s): SpillerTest 584 + 9 lightweight
   SpillerTest.cpp
-  SpillTest.cpp
-  SplitListenerTest.cpp
+  PlanNodeToSummaryStringTest.cpp
+  CountingJoinTest.cpp
+  CustomJoinTest.cpp
+  TaskListenerTest.cpp
   SplitTest.cpp
   SqlTest.cpp
-  StreamingAggregationTest.cpp
+  WindowFunctionRegistryTest.cpp
   StreamingEnforceDistinctTest.cpp
-  TableScanTest.cpp
+  HashBitRangeTest.cpp
+  # group4 (~575s): HashJoinTest ~575 + 9 lightweight
+  HashJoinTest.cpp
+  SpillTest.cpp
+  WindowTest.cpp
+  PrefixSortTest.cpp
+  MergerTest.cpp
+  LocalPartitionTest.cpp
+  PrintPlanWithStatsTest.cpp
+  ProbeOperatorStateTest.cpp
+  MarkDistinctTest.cpp
+  MergeTest.cpp
+  # group5 (~445s): TableWriterTest 225 + OutputBufMgr 98
+  # + TopNRowNumber 64 + StreamingAgg 58
   TableWriterTest.cpp
-  TaskListenerTest.cpp
-  ThreadDebugInfoTest.cpp
+  OutputBufferManagerTest.cpp
   TopNRowNumberTest.cpp
+  StreamingAggregationTest.cpp
+  ContainerRowSerdeTest.cpp
+  RowContainerTest.cpp
   TopNTest.cpp
+  WriterFuzzerUtilTest.cpp
+  PlanNodeStatsTest.cpp
+  ThreadDebugInfoTest.cpp
+  # group6 (~467s): TableScanTest 189 + AggregationTest 105
+  # + OrderBy 71 + HashTable 60 + RowNumber 42
+  TableScanTest.cpp
+  AggregationTest.cpp
+  OrderByTest.cpp
+  HashTableTest.cpp
+  RowNumberTest.cpp
   UnnestTest.cpp
-  UnorderedStreamReaderTest.cpp
-  ValuesTest.cpp
+  PlanNodeSerdeTest.cpp
+  HashJoinBridgeTest.cpp
+  SortBufferTest.cpp
   VectorHasherTest.cpp
-  WindowFunctionRegistryTest.cpp
-  WindowTest.cpp
-  WriterFuzzerUtilTest.cpp
+  # group7 (~449s): IndexLookupJoinTestExtra 188
+  # + MergeJoin 111 + ScaleWriter 96 + Exchange 54
+  IndexLookupJoinTestExtra.cpp
+  MergeJoinTest.cpp
+  ScaleWriterLocalPartitionTest.cpp
+  ExchangeClientTest.cpp
+  NestedLoopJoinTest.cpp
+  UnorderedStreamReaderTest.cpp
+  PlanNodeToStringTest.cpp
+  AssignUniqueIdTest.cpp
+  FilterProjectTest.cpp
+  AsyncConnectorTest.cpp
 )
 
 set(