Overview

The module allows you to analyze performance of individual query.

It stores in context structure:

{
    'enabled': True,
    'tree': {
        'start_at': 123456,
        'stop_at': None,
        'name': 'root node',
        'children': [{
            'start_at': 234567,
            'stop_at': None,
            'name': 'child node',
            'children': []
        }],
    },
    'pointer': [1],
    'level': 0
}

• enabled - is profiling enabled at the moment or not
• tree - nested dict with tree nodes
• pointer - list of integers which indicates index of node chiled on each level. Using that list is possible to get current node.
• level - interer, indicates how deep in the tree we are at the moment. This value is changing even if enabled is False. It required because enabled may be cahnged at any moment. If enabled is True then we start to collect nodes only if level == 1.

Also initial profiling structure may be expanded with additional keys using .set_meta method.

Tree node structure:

{
    'start_at': timestamp,
    'stop_at': timestamp,
    'name': str,
    'children': [list of nodes]
}

To start/stop collect info need to do:

set profiling=true;
-- execute investigated queries
set profiling=false;

API

There are 3 ways to use:

1. manually add start/stop in the code:

start('my tag')
function()
stop()

2. context:

with Context('my tag'):
    function()

3. decorator:

@profile('my tag')
def function():
    ...