Hotspot Function Analysis
Command Function
Uses ptrace to sample Python programs and Python & C/C++ hybrid programs, analyzes call stacks, obtains top 20 hotspot functions, and draws flame graphs.
- The supported Python versions are 3.7.X to 3.11.X.
- The supported OS is openEuler.
- Only the PID mode is supported for collection and analysis.
Syntax
1
|
devkit py-perf hotspot [-h] [-l {0,1,2,3}] [-d <sec>] [-i <msec>] [-p {PID}] [-o <file>] [-t] [--native] [--nolineno] |
Parameter Description
|
Parameter |
Option |
Description |
|---|---|---|
|
-h/--help |
- |
Obtains help information. This parameter is optional. |
|
-l/--log-level |
0/1/2/3 |
Log level, which defaults to 1. This parameter is optional.
|
|
-d/--duration |
- |
Collection duration, in seconds. The minimum value is 1 second. By default collection never ends. You can press Ctrl+\ to cancel the task or press Ctrl+C to stop the collection and start analysis. This parameter is optional. |
|
-i/--interval |
- |
Collection interval, in milliseconds. The value ranges from 1 to 1000 and the default value is 10. This parameter is optional. |
|
-p/--pid |
PID |
PID of the process to be collected. Only a single process can be collected. If the process to be collected has subprocesses, the subprocesses are not collected. This parameter is optional. |
|
-o/--output |
- |
Report file name. By default, the report file is generated in the current directory. The default file name format is FlameGraph-YMD-HMS. This parameter is optional. |
|
-t/--threads |
- |
Sets the report and flame graph to display call stack information by thread group, facilitating performance distribution analysis in multi-thread scenarios. This parameter is optional. |
|
--native |
- |
Indicates whether to collect Python and C call stacks. If this parameter is used, Python and C call stacks are collected. Otherwise, only Python call stacks are collected. This parameter is optional. |
|
--nolineno |
- |
Indicates that the report and flame graph do not display line numbers. This parameter is optional. |
Example
1
|
devkit py-perf hotspot -p 2082596 -d 5 -i 100 -o /home/demo/flamegraph -t --native |
- The -p 2082596 parameter collects information about the process whose ID is 2082596. The -d 5 parameter indicates that the collection duration is 5 seconds. The -i 100 parameter indicates that the collection interval is 100 milliseconds. The -o /home/demo/flamegraph parameter indicates that the flamegraph.html file is generated in /home/demo/. The -t parameter indicates that the report and flame graph display information per thread. The --native parameter indicates the Python and C call stack information is collected.
- The command output contains too much stack information, most of which has been omitted for easy reading. For the detailed information, see the actual command output.
Command output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 |
Press Ctrl+ \ to cancel the task or Ctrl+ C to stop the task collection and enter the analysis. Python Hotspot Top20 Summary Report Time:2024/11/18 10:39:07 ================================================================================ ──────────────────────────────────────────────────────────────────── Function Runtime(ms) Runtime(%) ──────────────────────────────────────────────────────────────────── Test::_calculate(int, double) 4814 95.96 Test::_calculate(int, double) (/home/workspace/pyhotspot_demo/simple-demo/test.cpp:18) Test::calculate(int, double, char*, int*, double*, char**) (/home/workspace/pyhotspot_demo/simple-demo/test.cpp:36) my_calculate (/home/workspace/pyhotspot_demo/simple-demo/test.cpp:47) ffi_prep_go_closure ffi_closure_free _ctypes_callproc (/home/Python-3.11.2/Modules/_ctypes/callproc.c:943) PyCFuncPtr_call (/home/Python-3.11.2/Modules/_ctypes/_ctypes.c:4212) _PyObject_MakeTpCall (/home/Python-3.11.2/./Include/internal/pycore_ceval.h:123) calculate (/home/demo/pyhotspot_demo/simple-demo/test.py:20) <module> (/home/demo/pyhotspot_demo/simple-demo/test.py:67) PyEval_EvalCode (/home/Python-3.11.2/./Include/internal/pycore_ceval.h:73) run_mod (/home/Python-3.11.2/Python/pythonrun.c:1714) _PyRun_SimpleFileObject (/home/Python-3.11.2/Python/pythonrun.c:1630) _PyRun_AnyFileObject (/home/Python-3.11.2/Python/pythonrun.c:79) pymain_run_python.constprop.0 (/home/Python-3.11.2/Modules/main.c:361) Py_BytesMain (/home/Python-3.11.2/Modules/main.c:682) __libc_init_first __libc_start_main _start Test::_calculate(int, double) 202 4.04 Test::_calculate(int, double) (/home/workspace/pyhotspot_demo/simple-demo/test.cpp:19) Test::calculate(int, double, char*, int*, double*, char**) (/home/workspace/pyhotspot_demo/simple-demo/test.cpp:36) my_calculate (/home/workspace/pyhotspot_demo/simple-demo/test.cpp:47) ffi_prep_go_closure ffi_closure_free _ctypes_callproc (/home/Python-3.11.2/Modules/_ctypes/callproc.c:943) PyCFuncPtr_call (/home/Python-3.11.2/Modules/_ctypes/_ctypes.c:4212) _PyObject_MakeTpCall (/home/Python-3.11.2/./Include/internal/pycore_ceval.h:123) calculate (/home/demo/pyhotspot_demo/simple-demo/test.py:20) <module> (/home/demo/pyhotspot_demo/simple-demo/test.py:67) PyEval_EvalCode (/home/Python-3.11.2/./Include/internal/pycore_ceval.h:73) run_mod (/home/Python-3.11.2/Python/pythonrun.c:1714) _PyRun_SimpleFileObject (/home/Python-3.11.2/Python/pythonrun.c:1630) _PyRun_AnyFileObject (/home/Python-3.11.2/Python/pythonrun.c:79) pymain_run_python.constprop.0 (/home/Python-3.11.2/Modules/main.c:361) Py_BytesMain (/home/Python-3.11.2/Modules/main.c:682) __libc_init_first __libc_start_main _start ──────────────────────────────────────────────────────────────────── The flamegraph html report: /home/demo/flamegraph.html |
You can use a browser to view the HTML file of the flame graph. Because the stack name is too long, you can move the mouse pointer over a stack block to view its information. You can also click a stack block to view its details.
