Metadata-Version: 1.1
Name: live-trace
Version: 2017.25.0
Summary: Trace a Python application using a deamon thread.
Home-page: https://github.com/guettli/live-trace/
Author: Thomas Guettler
Author-email: info.live-trace@thomas-guettler.de
License: Apache Software License 2.0
Description: .. image:: https://travis-ci.org/guettli/live-trace.svg?branch=master
            :target: https://travis-ci.org/guettli/live-trace
            
            
        live-trace
        ==========
        
        live-trace is a Python library to log stacktraces of a running application in a
        daemon thread N times per second.  The log file can be analyzed to see
        where the interpreter spends most of the time.  It is called
        "live-trace" since it can be used on production systems without
        noticeable performance impact.
        
        Alternatives
        ============
        
        Please, do not use live-trace any more. I recommend this:
        
        `py-spy <https://github.com/benfred/py-spy>`_ and `speedscope <https://github.com/jlfwong/speedscope>`_ for analyzing the profile graph.
        
        
        Why live trace?
        ===============
        
        If you want to see why a particular request is slow, then use a profiler, not live-trace.
        
        Use live-trace if you want to see the bird's-eye view. If you ask yourself the question:
        
          What is the interpreter doing all day long?
        
        Then use live-trace in your production environment. Let it collect a lot of snaphosts of the interpreter state.
        The current implementation uses stacktraces for freezing the state of the interpreter. 
        After running for some hours you can aggregate the collected stacktraces
        and identify hot spots.
        
        
        Usage
        =====
        
        Usage run-and-analyze::
        
            you@unix> live-trace run-and-analyze your-python-script.py
        
        Usage run, analyze later::
        
            you@unix> live-trace run your-python-script.py
        
            The collected stacktraces will be written to $TMP/live_trace/YYYY-MM-DD....log
        
            Now you can analyze the collected stacktraces:
        
            you@unix> live-trace analyze tmp/live_trace/2017-01-09-11-23-40.log
        
        Development
        ===========
        
        # Installing for development
        pip install -e git+https://github.com/guettli/live-trace.git#egg=live-trace
        
        # Running tests
        cd src/live-trace
        python setup.py test
        
        Django Middleware
        =================
        
        The django middleware is optional. The tool live-trace is a general python tool.
        If you want to use live-trace in other web frameworks, take this as template.
        
        You can start the watching thread your django middleware like this::
        
            MIDDLEWARE_CLASSES=[
                ...
                'live_trace.django_middleware.LiveTraceMiddleware',
            ]
        
        Optional, update the `settings.py`::
        
            live_trace_interval=0.1 # Default is every 0.3 second. Set to None to disable live-tracing.
        
        Example
        =======
        
        The tool does some guessing which code is from you, and which code is from Python or Django.
        
        Since Python and Django code is already optimized, your code gets highlighted with "<====".
        
        That's most likely your code and this could be a bottle neck::
        
             1971 File: "/home/foo_bar_p/django/core/handlers/wsgi.py", line 272, in __call__
                response = self.get_response(request)
             1812 File: "/home/foo_bar_p/django/core/handlers/base.py", line 111, in get_response
                response = callback(request, *callback_args, **callback_kwargs)
             1725 File: "/home/foo_bar_p/django/db/backends/postgresql_psycopg2/base.py", line 44, in execute
                return self.cursor.execute(query, args)
             1724 File: "/home/foo_bar_p/django/db/models/sql/compiler.py", line 735, in execute_sql
                cursor.execute(sql, params)
             1007 File: "/home/foo_bar_p/django/db/models/sql/compiler.py", line 680, in results_iter
                for rows in self.execute_sql(MULTI):
              796 File: "/home/foo_bar_p/django/db/models/query.py", line 273, in iterator
                for row in compiler.results_iter():
              763 File: "/home/foo_bar_p/foo/utils/ticketutils.py", line 135, in __init__    <====
                filter=type_filter(root_node=self.root_node)
              684 File: "/home/foo_bar_p/django/db/models/query.py", line 334, in count
                return self.query.get_count(using=self.db)
              679 File: "/home/foo_bar_p/django/db/models/sql/query.py", line 367, in get_aggregation
                result = query.get_compiler(using).execute_sql(SINGLE)
              677 File: "/home/foo_bar_p/django/db/models/sql/query.py", line 401, in get_count
                number = obj.get_aggregation(using=using)[None]
        
Platform: UNKNOWN
Classifier: Development Status :: 3 - Alpha
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
