pytrace - a fast python tracer

pytrace records function calls, arguments and return values.

traces aid debugging, profiling and obviate logging.

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Install

pytrace depends on sqlite and a C implementation of protocol buffers.

on debian/ubuntu: sudo apt-get install libsqlite3-dev libprotobuf-c0-dev

on mac (sqlite is included): brew install protobuf-c or port install protobuf-c

install pytrace:

pip install pytrace

Invoke pytrace with your script:

$ pytrace foo.py --bar

Invoke the reader from the same directory by executing pytrace with no arguments:

$ pytrace

The reader can be invoked while the script is running. providing 'online' debugging capabilities.

The collected data can be viewed in an interactive reader. The reader supports less-like key bindings.

The reader can search for regular expressions:

The reader can filter traces using a python syntax:

strings support comparison using the sql 'like' syntax: module == 'project.%'.
numbers support numeric operators: time > '2012/08/15 01:23:45'.

The reader corrects queries that don't match anything:

The database is saved in the current working directory and is named traces.sqlite.

In order to not run out of disk space, The database will be truncated to a fixed number of traces (currently hard coded to 10000).

Hot functions can be skipped using a decorator:

from pytrace import notrace

@notrace
def hot():
	pass

Trace specific packages:

$ export TRACE_MODULES=/Users/alon/project

You can specify a colon : separated list of folders as well.