org.apache.ignite.internal.processors.cache.persistence.pagemem

Class PagesWriteThrottle

java.lang.Object

org.apache.ignite.internal.processors.cache.persistence.pagemem.PagesWriteThrottle

All Implemented Interfaces:

PagesWriteThrottlePolicy

public class PagesWriteThrottle
extends Object
implements PagesWriteThrottlePolicy

Throttles threads that generate dirty pages during ongoing checkpoint. Designed to avoid zero dropdowns that can happen if checkpoint buffer is overflowed.

Field Summary

Fields inherited from interface org.apache.ignite.internal.processors.cache.persistence.pagemem.PagesWriteThrottlePolicy

CP_BUF_FILL_THRESHOLD, DFLT_THROTTLE_LOG_THRESHOLD, LOGGING_THRESHOLD

Constructor Summary

Constructors

Constructor and Description
PagesWriteThrottle(PageMemoryImpl pageMemory, IgniteOutClosure<CheckpointProgress> cpProgress, CheckpointLockStateChecker stateChecker, boolean throttleOnlyPagesInCheckpoint, IgniteLogger log)

Method Summary

Modifier and Type	Method and Description
boolean	isCpBufferOverflowThresholdExceeded() Whether Checkpoint Buffer is currently close to exhaustion.
void	onBeginCheckpoint() Callback to notify throttling policy checkpoint was started.
void	onFinishCheckpoint() Callback to notify throttling policy checkpoint was finished.
void	onMarkDirty(boolean isPageInCheckpoint) Callback to apply throttling delay.
void	wakeupThrottledThreads() Callback to wakeup throttled threads.

Methods inherited from class java.lang.Object

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

Constructor Detail

PagesWriteThrottle

public PagesWriteThrottle(PageMemoryImpl pageMemory,
                          IgniteOutClosure<CheckpointProgress> cpProgress,
                          CheckpointLockStateChecker stateChecker,
                          boolean throttleOnlyPagesInCheckpoint,
                          IgniteLogger log)

Parameters:

pageMemory - Page memory.

cpProgress - Database manager.

stateChecker - checkpoint lock state checker.

throttleOnlyPagesInCheckpoint - If true, throttle will only protect from checkpoint buffer overflow.

log - Logger.

Method Detail

onMarkDirty

public void onMarkDirty(boolean isPageInCheckpoint)

Callback to apply throttling delay.

Specified by:

onMarkDirty in interface PagesWriteThrottlePolicy

Parameters:

isPageInCheckpoint - flag indicating if current page is in scope of current checkpoint.

wakeupThrottledThreads

public void wakeupThrottledThreads()

Callback to wakeup throttled threads. Invoked when the Checkpoint Buffer use drops below a certain threshold.

Specified by:

wakeupThrottledThreads in interface PagesWriteThrottlePolicy

onBeginCheckpoint

public void onBeginCheckpoint()

Callback to notify throttling policy checkpoint was started.

Specified by:

onBeginCheckpoint in interface PagesWriteThrottlePolicy

onFinishCheckpoint

public void onFinishCheckpoint()

Callback to notify throttling policy checkpoint was finished.

Specified by:

onFinishCheckpoint in interface PagesWriteThrottlePolicy

isCpBufferOverflowThresholdExceeded

public boolean isCpBufferOverflowThresholdExceeded()

Whether Checkpoint Buffer is currently close to exhaustion.

Specified by:

isCpBufferOverflowThresholdExceeded in interface PagesWriteThrottlePolicy

Returns:

true if measures like throttling to protect Checkpoint Buffer should be applied, and false otherwise.