org.terracotta.async.configs
Class DefaultAsyncConfig

java.lang.Object
  org.terracotta.async.configs.DefaultAsyncConfig

All Implemented Interfaces:

AsyncConfig, AsyncConfig2

public class DefaultAsyncConfig
extends Object
implements AsyncConfig2

The default async configuration object.

The class can be subclasses to easily support configurations that differ only slightly from the default.

The default configuration has:

• A 1 second work delay
• Stealing enabled - with a 2 second maximum fall behind
• No batching
• Regular (non-synchronous) write locking
• No retrying
• No rate limiting

Field Summary

static int	BATCH_SIZE
static boolean	BATCHING_ENABLED
static long	MAX_ALLOWED_FALLBEHIND
static int	MAX_QUEUE_SIZE
static int	RATE_LIMIT
static long	RETRY_ATTEMPT_DELAY
static int	RETRY_ATTEMPTS
static boolean	STEALING_ENABLED
static boolean	SYNCHRONOUS_WRITE
static long	WORK_DELAY

Constructor Summary

protected

DefaultAsyncConfig()

Method Summary

int	getBatchSize() The number of items to include in each batch when batching is enabled.
static AsyncConfig	getInstance() Return an AsyncConfig instance representing the default configuration.
long	getMaxAllowedFallBehind() The maximum amount of time that a queue is allowed to fall behind on the work that it's processing.
int	getMaxQueueSize() The maximum size of items the Async coordinator can hold.
int	getRateLimit() Sets the maximum number of operations to allow per second when AsyncConfig.isBatchingEnabled() is enabled.
long	getRetryAttemptDelay() Retrieves the number of milliseconds to wait before retrying a failed operation.
int	getRetryAttempts() Retrieves the number of times the processing of an item os retried.
long	getWorkDelay() Returns the minimum amount of time to wait between individual work cycles.
boolean	isBatchingEnabled() Indicates whether to batch items.
boolean	isStealingEnabled() Indicates whether items can be stolen amongst queues or if each queue always has to process its own items
boolean	isSynchronousWrite() Perform all writes to the Terracotta backend in a synchronous fashion, hence increasing reliability but decreasing performance.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

WORK_DELAY

public static final long WORK_DELAY

See Also:

Constant Field Values

MAX_ALLOWED_FALLBEHIND

public static final long MAX_ALLOWED_FALLBEHIND

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Constant Field Values

STEALING_ENABLED

public static final boolean STEALING_ENABLED

See Also:

Constant Field Values

BATCH_SIZE

public static final int BATCH_SIZE

See Also:

Constant Field Values

BATCHING_ENABLED

public static final boolean BATCHING_ENABLED

See Also:

Constant Field Values

SYNCHRONOUS_WRITE

public static final boolean SYNCHRONOUS_WRITE

See Also:

Constant Field Values

RETRY_ATTEMPTS

public static final int RETRY_ATTEMPTS

See Also:

Constant Field Values

RETRY_ATTEMPT_DELAY

public static final long RETRY_ATTEMPT_DELAY

See Also:

Constant Field Values

RATE_LIMIT

public static final int RATE_LIMIT

See Also:

Constant Field Values

MAX_QUEUE_SIZE

public static final int MAX_QUEUE_SIZE

See Also:

Constant Field Values

Constructor Detail

DefaultAsyncConfig

protected DefaultAsyncConfig()

Method Detail

getInstance

public static AsyncConfig getInstance()

Return an AsyncConfig instance representing the default configuration.

Returns:

the default configuration

getWorkDelay

public long getWorkDelay()

Description copied from interface: AsyncConfig

Returns the minimum amount of time to wait between individual work cycles.

This allows work to accumulate in the write behind queue and be processed more efficiently.

Specified by:

getWorkDelay in interface AsyncConfig

Returns:

the work delay that should be used, in milliseconds

getMaxAllowedFallBehind

public long getMaxAllowedFallBehind()

Description copied from interface: AsyncConfig

The maximum amount of time that a queue is allowed to fall behind on the work that it's processing.

This parameter is used to determine if the outstanding work of a queue can be stolen by another queue in the cluster.

Specified by:

getMaxAllowedFallBehind in interface AsyncConfig

Returns:

the maximum of time that the queue is allowed to fall behind, in milliseconds

isStealingEnabled

public boolean isStealingEnabled()

Description copied from interface: AsyncConfig

Indicates whether items can be stolen amongst queues or if each queue always has to process its own items

Specified by:

isStealingEnabled in interface AsyncConfig

Returns:

true when stealing is enabled; or false otherwise

getBatchSize

public int getBatchSize()

Description copied from interface: AsyncConfig

The number of items to include in each batch when batching is enabled. If there are less entries in the queue than the batch size, the queue length size is used.

Specified by:

getBatchSize in interface AsyncConfig

Returns:

the amount of items to batch

isBatchingEnabled

public boolean isBatchingEnabled()

Description copied from interface: AsyncConfig

Indicates whether to batch items. If set to true, ItemProcessor.process(java.util.Collection) will be called rather than ItemProcessor.process(Object) being called for individual item. Resources such as databases can perform more efficiently if updates are batched, thus reducing load.

Specified by:

isBatchingEnabled in interface AsyncConfig

Returns:

true if items should be batched; false otherwise

isSynchronousWrite

public boolean isSynchronousWrite()

Description copied from interface: AsyncConfig

Perform all writes to the Terracotta backend in a synchronous fashion, hence increasing reliability but decreasing performance.

Specified by:

isSynchronousWrite in interface AsyncConfig

Returns:

true to enable synchronous writes; or false to perform the write asynchronously

getRetryAttempts

public int getRetryAttempts()

Description copied from interface: AsyncConfig

Retrieves the number of times the processing of an item os retried.

Specified by:

getRetryAttempts in interface AsyncConfig

Returns:

the number of tries before this pass is considered failed

getRetryAttemptDelay

public long getRetryAttemptDelay()

Description copied from interface: AsyncConfig

Retrieves the number of milliseconds to wait before retrying a failed operation.

Specified by:

getRetryAttemptDelay in interface AsyncConfig

Returns:

the delay in between retries, in milliseconds

getRateLimit

public int getRateLimit()

Description copied from interface: AsyncConfig

Sets the maximum number of operations to allow per second when AsyncConfig.isBatchingEnabled() is enabled.

Specified by:

getRateLimit in interface AsyncConfig

Returns:

the rate limit

getMaxQueueSize

public int getMaxQueueSize()

Description copied from interface: AsyncConfig2

The maximum size of items the Async coordinator can hold.

Specified by:

getMaxQueueSize in interface AsyncConfig2

Returns: