FIX: Flaky tests in CI and mark stress tests

eng/pipelines/pr-validation-pipeline.yml

@@ -621,6 +621,7 @@ jobs:
       python benchmarks/perf-benchmarking.py --baseline benchmark_baseline.json --json benchmark_results.json
     displayName: 'Run performance benchmarks on macOS $(sqlVersion)'
     condition: or(eq(variables['sqlVersion'], 'SQL2022'), eq(variables['sqlVersion'], 'SQL2025'))
+    timeoutInMinutes: 20
     continueOnError: true
     env:
       DB_CONNECTION_STRING: 'Server=tcp:127.0.0.1,1433;Database=AdventureWorks2022;Uid=SA;Pwd=$(DB_PASSWORD);TrustServerCertificate=yes'

tests/conftest.py

@@ -15,6 +15,25 @@
 import time
 
 
+def is_qemu_emulated():
+    """Detect if running under QEMU user-mode emulation (e.g. ARM64 on x86_64 host).
+
+    QEMU reports CPU implementer 0x51 in /proc/cpuinfo. Native ARM64 hardware
+    uses vendor-specific IDs (0x41 ARM, 0x61 Apple, etc.).
+    """
+    try:
+        with open("/proc/cpuinfo") as f:
+            for line in f:
+                if line.startswith("CPU implementer") and "0x51" in line:
+                    return True
+    except (FileNotFoundError, PermissionError):
+        pass
+    return False
+
+
+QEMU = is_qemu_emulated()
+
+
 def is_azure_sql_connection(conn_str):
     """Helper function to detect if connection string is for Azure SQL Database"""
     if not conn_str:

tests/test_013_SqlHandle_free_shutdown.py

@@ -34,7 +34,13 @@
 
 import pytest
 
+from conftest import QEMU
 
+
+@pytest.mark.skipif(
+    QEMU,
+    reason="Subprocess shutdown tests SIGSEGV under QEMU user-mode emulation — not reproducible on native ARM64",
+)
 class TestHandleFreeShutdown:
     """Test SqlHandle::free() behavior for all handle types during Python shutdown."""
 
@@ -85,7 +91,7 @@ def test_aggressive_dbc_segfault_reproduction(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         # Check for segfault
@@ -141,7 +147,7 @@ def on_exit():
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         if result.returncode < 0:
@@ -205,7 +211,7 @@ def test_force_gc_finalization_order_issue(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         if result.returncode < 0:
@@ -247,7 +253,7 @@ def test_stmt_handle_cleanup_at_shutdown(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -290,7 +296,7 @@ def test_dbc_handle_cleanup_at_shutdown(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -338,7 +344,7 @@ def test_env_handle_cleanup_at_shutdown(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -410,7 +416,7 @@ def test_mixed_handle_cleanup_at_shutdown(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -463,7 +469,7 @@ def test_rapid_connection_churn_with_shutdown(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -502,7 +508,7 @@ def test_exception_during_query_with_shutdown(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -555,7 +561,7 @@ def callback(ref):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -613,7 +619,7 @@ def execute_query(self):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -685,7 +691,7 @@ def test_all_handle_types_comprehensive(self, conn_str):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=5
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Process crashed. stderr: {result.stderr}"
@@ -940,7 +946,7 @@ def test_cleanup_connections_scenarios(self, conn_str, scenario, test_code, expe
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=3
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Test failed. stderr: {result.stderr}"
@@ -1126,7 +1132,7 @@ def close(self):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=3
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Test failed. stderr: {result.stderr}"
@@ -1216,7 +1222,7 @@ def close(self):
         """)
 
         result = subprocess.run(
-            [sys.executable, "-c", script], capture_output=True, text=True, timeout=3
+            [sys.executable, "-c", script], capture_output=True, text=True, timeout=15
         )
 
         assert result.returncode == 0, f"Test failed. stderr: {result.stderr}"

tests/test_022_concurrent_query_gil_release.py

@@ -70,6 +70,7 @@ def _run_waitfor(conn_str: str) -> float:
 # ============================================================================
 
 
+@pytest.mark.stress  # Heartbeat tick counts flake under CI CPU contention (macOS Py3.14)
 def test_query_does_not_block_other_python_threads(conn_str):
     """
     While one thread executes a 2-second ``WAITFOR DELAY``, a second pure-Python
@@ -134,6 +135,7 @@ def run_query():
 # ============================================================================
 
 
+@pytest.mark.stress  # Heartbeat tick counts flake under CI CPU contention (macOS Py3.14)
 def test_commit_does_not_block_other_python_threads(conn_str):
     """
     Smoke test for the SQLEndTran GIL-release added to ``Connection::commit``