**Description**


It would be great if the metrics we publish in Airflow change to include TAGs for "variable" parts of those (such as dag_id, task_id, pool name) rather than being part of the metrics.

See here: https://airflow.apache.org/docs/1.10.12/metrics.html, https://airflow.readthedocs.io/en/latest/logging-monitoring/metrics.html  - those variable parts should be tags.

We might consider to change those metrics by default in 2.0 and possibly introduce a backport in 1.10.13 to allow people to migrate.


**Use case / motivation**

Having the variable parts of the metrics makes it really difficult to aggregate the metrics. Seems that statsd python library does not support tags, but there are possible solutions by installing extensions:

https://stackoverflow.com/questions/49852654/sending-statsd-metrics-with-tags-from-python-client

**Related Issues**

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self,
        dag_run: DagRun,
        session: Session,
    ) -> DagCallbackRequest | None:
        """
        Make scheduling decisions about an individual dag run.
        :param dag_run: The DagRun to schedule
        :return: Callback that needs to be executed
        """
        callback: DagCallbackRequest | None = None
        dag = dag_run.dag = self.dagbag.get_dag(dag_run.dag_id, session=session)
        if not dag:
            self.log.error("Couldn't find dag %s in DagBag/DB!", dag_run.dag_id)
            return callback
        dag_model = DM.get_dagmodel(dag.dag_id, session)
        if (
            dag_run.start_date
            and dag.dagrun_timeout
            and dag_run.start_date < timezone.utcnow() - dag.dagrun_timeout
        ):
            dag_run.set_state(DagRunState.FAILED)
            unfinished_task_instances = (
                session.query(TI)
                .filter(TI.dag_id == dag_run.dag_id)
                .filter(TI.run_id == dag_run.run_id)