pyliveupdate

PyLiveUpdate is a dynamic code manipulation (e.g. bytecode instrumentation) framework for profiling, debugging and bugfixing Python programs.

PyLiveUpdate allows developers to profile, diagnose and fix production issues for Python programs without restarting the programs.

Demo

Key features

• Profile specific Python functions' (by function names or module names) call time.
• Add / remove profilings without restart programs.
• Show profiling results with call summary and flamegraphs.
• More features are under developing. (Let us know what features you want: devopspp#2)

Quick start

Compatibility

• Supports Python 3.5+ on Linux.

Install

pip install pyliveupdate

or

git clone https://github.com/devopspp/pyliveupdate.git
pip install -e pyliveupdate

How to use

We currently implemented function profiling and are implementing more. Please feel free to let us know if you find other features useful: devopspp#2.

profile function call time

1. Start pyliveupdate server

pylu-controller -l

2. In your program (like examples/program1.py) main module add

from pyliveupdate import UpdateStub
from pyliveupdatescripts import FP
UpdateStub().start()

3. Run your program (make sure in the correct directory)

cd examples
python program1.py

4. Start profile a set of functions

FP.profile(['__main__.**', 'module1.**'])

or any functions

FP.profile('**')

6. List applied profiling

FP.ls()

7. Stop a profiling by its id without stopping your program

FP.revert(1)

8. Process the logs to generate a summary and a flamegraph

pylu-processlogs -i /tmp/pyliveupdate.log

9. View the generated call summary and flamegraph

Function call summary

The following summary gives in process 4510 thread 5, views.results was called 10 times and each time takes 139 ms, views.results called manager.all for 20 times.

4510-Thread-5
function  hit  time/hit (ms)
views.results 10  138.562
  -manager.all 20  14.212
    -__init__.__hash__ 10  0.035
    -manager.get_queryset 20  0.922
      -query.__init__ 20  0.616
        -query.__init__ 20  0.071

Flamegraph

Profiling scope

1. One specific function: module1.class1.func1
2. All functions in a class: module1.class1.*
3. All functions in a module: module1.**

* means one-level nesting, ** means any level of nesting.

Known Users

Welcome to register your company/organization name here: devopspp#1