feat(profiling): mark v1 profiler to be deprecated (#15055)

## Description

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## Testing

<!-- Describe your testing strategy or note what tests are included -->

## Risks

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-->

## Additional Notes

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---------

Co-authored-by: Nick Ripley <[email protected]>

Author: taegyunkim

ddtrace/settings/profiling.py

@@ -85,6 +85,31 @@ def _parse_profiling_enabled(raw: str) -> bool:
     return False
 
 
+def _parse_v2_enabled(raw: str) -> bool:
+    if sys.version_info >= (3, 14):
+        return False
+
+    # Parse the boolean value
+    raw_lc = raw.lower()
+    enabled = raw_lc in ("1", "true", "yes", "on")
+
+    # Warn if user explicitly disabled v2 profiler (v1 is deprecated)
+    if raw_lc in ("false", "0", "no", "off"):
+        from ddtrace.internal.utils.deprecations import DDTraceDeprecationWarning
+        from ddtrace.vendor.debtcollector import deprecate
+
+        deprecate(
+            "Setting DD_PROFILING_STACK_V2_ENABLED=false is deprecated",
+            message="The v1 stack profiler is deprecated and will be removed in a future version. "
+            "Please migrate to the v2 stack profiler by removing DD_PROFILING_STACK_V2_ENABLED=false "
+            "or setting it to true.",
+            category=DDTraceDeprecationWarning,
+            removal_version="4.0.0",
+        )
+
+    return enabled
+
+
 def _update_git_metadata_tags(tags):
     """
     Update profiler tags with git metadata
@@ -261,6 +286,7 @@ class ProfilingConfigStack(DDConfig):
     _v2_enabled = DDConfig.v(
         bool,
         "v2_enabled",
+        parser=_parse_v2_enabled,
         # Not yet supported on 3.14
         default=sys.version_info < (3, 14),
         help_type="Boolean",

releasenotes/notes/profiling-v1-deprecate-f02a9d4d757534d9.yaml

@@ -0,0 +1,6 @@
+---
+deprecations:
+  - |
+    profiling: The V1 stack profiler is deprecated and will be removed in 4.0.
+    V2 has been enabled by default since v2.20.0.
+    ``DD_PROFILING_STACK_V2_ENABLED=false`` will no longer have an effect starting in 4.0.

tests/profiling/test_profiler.py

@@ -5,7 +5,6 @@
 import pytest
 
 import ddtrace
-from ddtrace.internal.compat import PYTHON_VERSION_INFO
 from ddtrace.profiling import collector
 from ddtrace.profiling import profiler
 from ddtrace.profiling import scheduler
@@ -146,25 +145,3 @@ def test_profiler_serverless(monkeypatch):
     p = profiler.Profiler()
     assert isinstance(p._scheduler, scheduler.ServerlessScheduler)
     assert p.tags["functionname"] == "foobar"
-
-
-@pytest.mark.skipif(PYTHON_VERSION_INFO < (3, 9), reason="Python 3.8 throws a deprecation warning")
-@pytest.mark.subprocess()
-def test_profiler_ddtrace_deprecation():
-    """
-    ddtrace interfaces loaded by the profiler can be marked deprecated, and we should update
-    them when this happens.  As reported by https://github.com/DataDog/dd-trace-py/issues/8881
-    """
-    import warnings
-
-    with warnings.catch_warnings():
-        warnings.simplefilter("error", DeprecationWarning)
-        from ddtrace.profiling import _threading  # noqa:F401
-        from ddtrace.profiling import event  # noqa:F401
-        from ddtrace.profiling import profiler  # noqa:F401
-        from ddtrace.profiling import scheduler  # noqa:F401
-        from ddtrace.profiling.collector import _lock  # noqa:F401
-        from ddtrace.profiling.collector import _task  # noqa:F401
-        from ddtrace.profiling.collector import _traceback  # noqa:F401
-        from ddtrace.profiling.collector import memalloc  # noqa:F401
-        from ddtrace.profiling.collector import stack  # noqa:F401