docs/usage_guide/advanced_usage/modin_metrics.rst
Modin allows for third-party systems to register a metrics handler to collect specific API statistics. Metrics have a name and a value, can be aggregated, discarded, or emitted without impact to the program.
CPU load, memory usage, and disk usage are all typical metrics; but modin currently only emits metrics on API timings which can be used to optimize end-user interactive performance. New metrics may be added in the future.
It is the responsibility of the handler to process or forward these metrics. The name of the metric will be in "dot format" and all lowercase, similar to graphite or rrd. The value is an integer or float.
Example metric names include:
Handlers are functions of the form: fn(str, int|float) and can be registered with:
.. code-block:: python
import modin.pandas as pd from modin.logging.metrics import add_metric_handler
def func(name: str, value: int | float): print(f"Got metric {name} value {value}")
add_metric_handler(func)
.. warning:: A metric handler should be non-blocking, returning within 100ms, although this is not enforced. It must not throw exceptions or it will be deregistered. These restrictions are to help guard against the implementation of a metrics collector which would impact interactice performance significantly. The data from metrics should generally be offloaded to another system for processing and not involve any blocking network calls.
Metrics are enabled by default. Modin metrics can be disabled like so:
.. code-block:: python
import modin.pandas as pd from modin.config import MetricsMode MetricsMode.disable()