Lee Hinman 623d3700f0
Add accounting circuit breaker and track segment memory usage (#27116)
* Add accounting circuit breaker and track segment memory usage

This commit adds a new circuit breaker "accounting" that is used for tracking
the memory usage of non-request-tied memory users. It also adds tracking for the
amount of Lucene segment memory used by a shard as a user of the new circuit
breaker.

The Lucene segment memory is updated when the shard refreshes, and removed when
the shard relocates away from a node or is deleted. It should also be noted that
all tracking for segment memory uses `addWithoutBreaking` so as not to fail the
shard if a limit is reached.

The `accounting` breaker has a default limit of 100% and will contribute to the
parent breaker limit.

Resolves #27044
2017-12-01 07:59:45 -07:00
..