chore(profiling): update echion (for memcpy) (#15030)

KowalskiThomas · web-flow · commit 7d7d92ec4003 · 2025-11-05T09:41:41.000Z
## Description This PR updates `dd-trace-py` to use the latest version of Echion. **New commits** * [echion/perf: use memcpy instead of process_vm_readv](P403n1x87/echion#162) ### Notes The main change is the new "fast memory copy" feature that significantly reduces the time it takes to copy memory from the Python process by using a SEGV-guarded `memcpy` (no system call involved) instead of `process_vm_readv`. This feature is **experimental** and we intend to test it within Datadog before making it widely available (and eventually, hopefully making it the default/only available option). Currently, `ddtrace` cannot enable/disable the feature itself; the Echion library relies on the `ECHION_USE_FAST_COPY_MEMORY` environment variable on startup to enable/disable it. ## Testing The change has been tested on benchmarks, in the CI and inside the reliability environment. No crashes are happening.
diff --git a/.github/workflows/profiling-native.yml b/.github/workflows/profiling-native.yml
@@ -21,6 +21,7 @@ jobs:
       matrix:
         os: [ubuntu-24.04]
         python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
+        memcpy-mode: ["default", "fast"]
         sanitizer: ["safety", "thread", "valgrind"]
 
     steps:
@@ -49,4 +50,10 @@ jobs:
           # DEV: We currently have tests in dd_wrapper and stack_v2, setting
           # stack_v2 here will also run tests in dd_wrapper. Revisit this when
           # that changes.
+          if [ "${{matrix.memcpy-mode}}" == "fast" ]; then
+            export ECHION_USE_FAST_COPY_MEMORY=1
+          else
+            export ECHION_USE_FAST_COPY_MEMORY=0
+          fi
+
           ./ddtrace/internal/datadog/profiling/build_standalone.sh --${{matrix.sanitizer}} RelWithDebInfo stack_v2_test
diff --git a/.riot/requirements/1217de7.txt b/.riot/requirements/1217de7.txt
@@ -0,0 +1,36 @@
+#
+# This file is autogenerated by pip-compile with Python 3.9
+# by the following command:
+#
+#    pip-compile --allow-unsafe --no-annotate .riot/requirements/1217de7.in
+#
+attrs==25.4.0
+coverage[toml]==7.10.7
+exceptiongroup==1.3.0
+gunicorn==23.0.0
+hypothesis==6.45.0
+importlib-metadata==8.7.0
+iniconfig==2.1.0
+jsonschema==4.25.1
+jsonschema-specifications==2025.9.1
+lz4==4.4.5
+mock==5.2.0
+opentracing==2.4.0
+packaging==25.0
+pluggy==1.6.0
+py-cpuinfo==8.0.0
+pygments==2.19.2
+pytest==8.4.2
+pytest-asyncio==0.21.1
+pytest-benchmark==5.2.1
+pytest-cov==7.0.0
+pytest-cpp==2.6.0
+pytest-mock==3.15.1
+pytest-randomly==4.0.1
+referencing==0.36.2
+rpds-py==0.27.1
+sortedcontainers==2.4.0
+tomli==2.3.0
+typing-extensions==4.15.0
+uwsgi==2.0.31
+zipp==3.23.0
diff --git a/.riot/requirements/147b755.txt b/.riot/requirements/147b755.txt
@@ -0,0 +1,32 @@
+#
+# This file is autogenerated by pip-compile with Python 3.12
+# by the following command:
+#
+#    pip-compile --allow-unsafe --no-annotate .riot/requirements/147b755.in
+#
+attrs==25.4.0
+coverage[toml]==7.11.0
+gunicorn==23.0.0
+hypothesis==6.45.0
+iniconfig==2.3.0
+jsonschema==4.25.1
+jsonschema-specifications==2025.9.1
+lz4==4.4.5
+mock==5.2.0
+opentracing==2.4.0
+packaging==25.0
+pluggy==1.6.0
+py-cpuinfo==8.0.0
+pygments==2.19.2
+pytest==8.4.2
+pytest-asyncio==0.21.1
+pytest-benchmark==5.2.1
+pytest-cov==7.0.0
+pytest-cpp==2.6.0
+pytest-mock==3.15.1
+pytest-randomly==4.0.1
+referencing==0.37.0
+rpds-py==0.28.0
+sortedcontainers==2.4.0
+typing-extensions==4.15.0
+uwsgi==2.0.31
diff --git a/.riot/requirements/1aa6d22.txt b/.riot/requirements/1aa6d22.txt
@@ -0,0 +1,31 @@
+#
+# This file is autogenerated by pip-compile with Python 3.13
+# by the following command:
+#
+#    pip-compile --allow-unsafe --no-annotate .riot/requirements/1aa6d22.in
+#
+attrs==25.4.0
+coverage[toml]==7.11.0
+gunicorn==23.0.0
+hypothesis==6.45.0
+iniconfig==2.3.0
+jsonschema==4.25.1
+jsonschema-specifications==2025.9.1
+lz4==4.4.5
+mock==5.2.0
+opentracing==2.4.0
+packaging==25.0
+pluggy==1.6.0
+py-cpuinfo==8.0.0
+pygments==2.19.2
+pytest==8.4.2
+pytest-asyncio==0.21.1
+pytest-benchmark==5.2.1
+pytest-cov==7.0.0
+pytest-cpp==2.6.0
+pytest-mock==3.15.1
+pytest-randomly==4.0.1
+referencing==0.37.0
+rpds-py==0.28.0
+sortedcontainers==2.4.0
+uwsgi==2.0.31
diff --git a/.riot/requirements/1df66ab.txt b/.riot/requirements/1df66ab.txt
@@ -0,0 +1,32 @@
+#
+# This file is autogenerated by pip-compile with Python 3.11
+# by the following command:
+#
+#    pip-compile --allow-unsafe --no-annotate .riot/requirements/1df66ab.in
+#
+attrs==25.4.0
+coverage[toml]==7.11.0
+gunicorn==23.0.0
+hypothesis==6.45.0
+iniconfig==2.3.0
+jsonschema==4.25.1
+jsonschema-specifications==2025.9.1
+lz4==4.4.5
+mock==5.2.0
+opentracing==2.4.0
+packaging==25.0
+pluggy==1.6.0
+py-cpuinfo==8.0.0
+pygments==2.19.2
+pytest==8.4.2
+pytest-asyncio==0.21.1
+pytest-benchmark==5.2.1
+pytest-cov==7.0.0
+pytest-cpp==2.6.0
+pytest-mock==3.15.1
+pytest-randomly==4.0.1
+referencing==0.37.0
+rpds-py==0.28.0
+sortedcontainers==2.4.0
+typing-extensions==4.15.0
+uwsgi==2.0.31
diff --git a/.riot/requirements/ea5d060.txt b/.riot/requirements/ea5d060.txt
@@ -0,0 +1,37 @@
+#
+# This file is autogenerated by pip-compile with Python 3.8
+# by the following command:
+#
+#    pip-compile --allow-unsafe --no-annotate .riot/requirements/ea5d060.in
+#
+attrs==25.3.0
+coverage[toml]==7.6.1
+exceptiongroup==1.3.0
+gunicorn==23.0.0
+hypothesis==6.45.0
+importlib-metadata==8.5.0
+importlib-resources==6.4.5
+iniconfig==2.1.0
+jsonschema==4.23.0
+jsonschema-specifications==2023.12.1
+lz4==4.3.3
+mock==5.2.0
+opentracing==2.4.0
+packaging==25.0
+pkgutil-resolve-name==1.3.10
+pluggy==1.5.0
+py-cpuinfo==8.0.0
+pytest==8.3.5
+pytest-asyncio==0.21.1
+pytest-benchmark==4.0.0
+pytest-cov==5.0.0
+pytest-cpp==2.6.0
+pytest-mock==3.14.1
+pytest-randomly==3.15.0
+referencing==0.35.1
+rpds-py==0.20.1
+sortedcontainers==2.4.0
+tomli==2.3.0
+typing-extensions==4.13.2
+uwsgi==2.0.31
+zipp==3.20.2
diff --git a/.riot/requirements/fa272ae.txt b/.riot/requirements/fa272ae.txt
@@ -0,0 +1,34 @@
+#
+# This file is autogenerated by pip-compile with Python 3.10
+# by the following command:
+#
+#    pip-compile --allow-unsafe --no-annotate .riot/requirements/fa272ae.in
+#
+attrs==25.4.0
+coverage[toml]==7.11.0
+exceptiongroup==1.3.0
+gunicorn==23.0.0
+hypothesis==6.45.0
+iniconfig==2.3.0
+jsonschema==4.25.1
+jsonschema-specifications==2025.9.1
+lz4==4.4.5
+mock==5.2.0
+opentracing==2.4.0
+packaging==25.0
+pluggy==1.6.0
+py-cpuinfo==8.0.0
+pygments==2.19.2
+pytest==8.4.2
+pytest-asyncio==0.21.1
+pytest-benchmark==5.2.1
+pytest-cov==7.0.0
+pytest-cpp==2.6.0
+pytest-mock==3.15.1
+pytest-randomly==4.0.1
+referencing==0.37.0
+rpds-py==0.28.0
+sortedcontainers==2.4.0
+tomli==2.3.0
+typing-extensions==4.15.0
+uwsgi==2.0.31
diff --git a/ddtrace/internal/datadog/profiling/stack_v2/CMakeLists.txt b/ddtrace/internal/datadog/profiling/stack_v2/CMakeLists.txt
@@ -49,7 +49,7 @@ endif()
 
 # Add echion
 set(ECHION_COMMIT
-    "1b02a8fcccaa4b748b494f3c3177b78be6503967" # https://github.com/P403n1x87/echion/commit/1b02a8fcccaa4b748b494f3c3177b78be6503967
+    "43432c5c0a89617b06533215a15d0d6ffbbfd02b" # https://github.com/P403n1x87/echion/commit/43432c5c0a89617b06533215a15d0d6ffbbfd02b
     CACHE STRING "Commit hash of echion to use")
 FetchContent_Declare(
     echion
@@ -62,8 +62,15 @@ if(NOT echion_POPULATED)
 endif()
 
 # Specify the target C-extension that we want to build
-add_library(${EXTENSION_NAME} SHARED ${echion_SOURCE_DIR}/echion/frame.cc ${echion_SOURCE_DIR}/echion/render.cc
-                                     src/sampler.cpp src/stack_renderer.cpp src/stack_v2.cpp src/thread_span_links.cpp)
+add_library(
+    ${EXTENSION_NAME} SHARED
+    ${echion_SOURCE_DIR}/echion/frame.cc
+    ${echion_SOURCE_DIR}/echion/render.cc
+    ${echion_SOURCE_DIR}/echion/danger.cc
+    src/sampler.cpp
+    src/stack_renderer.cpp
+    src/stack_v2.cpp
+    src/thread_span_links.cpp)
 
 # Add common config
 add_ddup_config(${EXTENSION_NAME})
diff --git a/releasenotes/notes/profiling-update-echion-1cb85860b04f891d.yaml b/releasenotes/notes/profiling-update-echion-1cb85860b04f891d.yaml
@@ -0,0 +1,5 @@
+upgrade:
+  - |
+    profiling: this updates echion (the Python stack sampler) to the latest version, which introduces an experimental
+    faster memory copy function.
+
diff --git a/riotfile.py b/riotfile.py
@@ -3474,6 +3474,12 @@ def select_pys(min_version: str = MIN_PYTHON_VERSION, max_version: str = MAX_PYT
                                 "gevent": latest,
                             },
                         ),
+                        # memcpy-based sampler
+                        Venv(
+                            env={
+                                "ECHION_USE_FAST_COPY_MEMORY": "1",
+                            },
+                        ),
                     ],
                 ),
                 # Python 3.10
@@ -3506,6 +3512,12 @@ def select_pys(min_version: str = MIN_PYTHON_VERSION, max_version: str = MAX_PYT
                                 ),
                             ],
                         ),
+                        # memcpy-based sampler
+                        Venv(
+                            env={
+                                "ECHION_USE_FAST_COPY_MEMORY": "1",
+                            },
+                        ),
                     ],
                 ),
                 # Python >= 3.11
@@ -3525,6 +3537,12 @@ def select_pys(min_version: str = MIN_PYTHON_VERSION, max_version: str = MAX_PYT
                             },
                             pkgs={"gunicorn[gevent]": latest, "gevent": latest},
                         ),
+                        # memcpy-based sampler
+                        Venv(
+                            env={
+                                "ECHION_USE_FAST_COPY_MEMORY": "1",
+                            },
+                        ),
                     ],
                 ),
                 Venv(
