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Not under active development

About

Mmstats is a way to expose and read diagnostic values and metrics for applications.

Think of mmstats as /proc for your application and the readers as procps utilities.

This project is a Python implementation, but compatible implementations can be made in any language (see Goals).

Discuss at https://groups.google.com/group/python-introspection

Goals

• Separate publishing/writing from consuming/reading tools
• Platform/language independent (a Java writer can be read by a Python tool)
• Predictable performance impact for writers via:
  • No locks (1 writer per thread)
  • No syscalls (after instantiation)
  • All in userspace
  • Reading has no impact on writers
• Optional persistent (writer can sync anytime)
• 1-way (Publish/consume only; mmstats are not management extensions)

Usage

Requirements

CPython 2.6 or 2.7 (Windows is untested)

PyPy (only tested in 1.7, should be faster in 1.8)

Using

1. easy_install mmstats or pip install mmstats or if you've downloaded the source: python setup.py install
2. Then in your Python project create a sublcass of mmstats.MmStats like

import mmstats

class WebStats(mmstats.MmStats):
    status2xx = mmstats.CounterField(label='status.2XX')
    status3xx = mmstats.CounterField(label='status.3XX')
    status4xx = mmstats.CounterField(label='status.4XX')
    status5xx = mmstats.CounterField(label='status.5XX')
    last_hit = mmstats.DoubleField(label='timers.last_hit')

3. Instantiate it once per process: (instances are automatically thread local)

webstats = WebStats(label_prefix='web.stats.')

4. Record some data:

if response.status_code == 200:
    webstats.status2xx.inc()

webstats.last_hit = time.time()

5. Run slurpstats to read it
6. Run mmash to create a web interface for stats
7. Run pollstats -p web.stats.status 2XX,3XX,4XX,5XX /tmp/mmstats-* for a vmstat/dstat like view.
8. Did a process die unexpectedly and leave around a stale mmstat file? cleanstats /path/to/mmstat/files will check to see which files are stale and remove them.