Package org.elasticsearch.common.breaker

Interface CircuitBreaker

All Known Implementing Classes:

ChildMemoryCircuitBreaker, MemoryCircuitBreaker, NoopCircuitBreaker

public interface CircuitBreaker

Interface for an object that can be incremented, breaking after some configured limit has been reached.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	CircuitBreaker.Type

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	ACCOUNTING	The accounting breaker tracks things held in memory that is independent of the request lifecycle.
static java.lang.String	FIELDDATA	The fielddata breaker tracks data used for fielddata (on fields) as well as the id cached used for parent/child queries.
static java.lang.String	IN_FLIGHT_REQUESTS	The in-flight request breaker tracks bytes allocated for reading and writing requests on the network layer.
static java.lang.String	PARENT	The parent breaker is a sum of all the following breakers combined.
static java.lang.String	REQUEST	The request breaker tracks memory used for particular requests.

Method Summary

Modifier and Type	Method	Description
double	addEstimateBytesAndMaybeBreak(long bytes, java.lang.String label)	add bytes to the breaker and maybe trip
long	addWithoutBreaking(long bytes)	Adjust the circuit breaker without tripping
void	circuitBreak(java.lang.String fieldName, long bytesNeeded)	Trip the circuit breaker
long	getLimit()
java.lang.String	getName()
double	getOverhead()
long	getTrippedCount()
long	getUsed()

Field Detail

PARENT

static final java.lang.String PARENT

The parent breaker is a sum of all the following breakers combined. With this we allow a single breaker to have a significant amount of memory available while still having a "total" limit for all breakers. Note that it's not a "real" breaker in that it cannot be added to or subtracted from by itself.

See Also:

Constant Field Values

FIELDDATA

static final java.lang.String FIELDDATA

The fielddata breaker tracks data used for fielddata (on fields) as well as the id cached used for parent/child queries.

See Also:

Constant Field Values

REQUEST

static final java.lang.String REQUEST

The request breaker tracks memory used for particular requests. This includes allocations for things like the cardinality aggregation, and accounting for the number of buckets used in an aggregation request. Generally the amounts added to this breaker are released after a request is finished.

See Also:

Constant Field Values

IN_FLIGHT_REQUESTS

static final java.lang.String IN_FLIGHT_REQUESTS

The in-flight request breaker tracks bytes allocated for reading and writing requests on the network layer.

See Also:

Constant Field Values

ACCOUNTING

static final java.lang.String ACCOUNTING

The accounting breaker tracks things held in memory that is independent of the request lifecycle. This includes memory used by Lucene for segments.

See Also:

Constant Field Values

Method Detail

circuitBreak

void circuitBreak(java.lang.String fieldName,
                  long bytesNeeded)

Trip the circuit breaker

Parameters:

fieldName - name of the field responsible for tripping the breaker

bytesNeeded - bytes asked for but unable to be allocated

addEstimateBytesAndMaybeBreak

double addEstimateBytesAndMaybeBreak(long bytes,
                                     java.lang.String label)
                              throws CircuitBreakingException

add bytes to the breaker and maybe trip

Parameters:

bytes - number of bytes to add

label - string label describing the bytes being added

Returns:

the number of "used" bytes for the circuit breaker

Throws:

CircuitBreakingException

addWithoutBreaking

long addWithoutBreaking(long bytes)

Adjust the circuit breaker without tripping

getUsed

long getUsed()

Returns:

the currently used bytes the breaker is tracking

getLimit

long getLimit()

Returns:

maximum number of bytes the circuit breaker can track before tripping

getOverhead

double getOverhead()

Returns:

overhead of circuit breaker

getTrippedCount

long getTrippedCount()

Returns:

the number of times the circuit breaker has been tripped

getName

java.lang.String getName()

Returns:

the name of the breaker