Package org.camunda.bpm.engine.impl.cmd

Class HistoryCleanupCmd

java.lang.Object

org.camunda.bpm.engine.impl.cmd.HistoryCleanupCmd

All Implemented Interfaces:

Command<Job>

public class HistoryCleanupCmd
extends Object
implements Command<Job>

Author:

Svetlana Dorokhova

Field Summary

Fields

Modifier and Type	Field	Description
static final JobDeclaration	HISTORY_CLEANUP_JOB_DECLARATION
static final int	MAX_THREADS_NUMBER

Constructor Summary

Constructors

Constructor	Description
HistoryCleanupCmd(boolean immediatelyDue)

Method Summary

Modifier and Type	Method	Description
protected void	acquireExclusiveLock(CommandContext commandContext)
protected HistoryCleanupContext	createCleanupContext(int[] minuteChunk, int maxRetries)
protected JobEntity	createJob(int[] minuteChunk, int maxRetries)
protected List<Job>	createJobs(int[][] minuteChunks)
Job	execute(CommandContext context)
protected List<Job>	getHistoryCleanupJobs()
boolean	isRetryable()	When CockroachDB is used, this command may be retried multiple times until it is successful, or the retries are exhausted.
protected List<Job>	reconfigureJobs(List<Job> historyCleanupJobs, int degreeOfParallelism, int[][] minuteChunks)
protected boolean	shouldCreateJobs(List<Job> jobs)
protected boolean	shouldReconfigureJobs(List<Job> jobs)
protected boolean	shouldSuspendJobs(List<Job> jobs)
protected void	suspendJobs(List<Job> jobs)
protected boolean	willBeScheduled()
protected void	writeUserOperationLog(CommandContext commandContext)

Methods inherited from class java.lang.Object

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

Field Details

HISTORY_CLEANUP_JOB_DECLARATION

public static final JobDeclaration HISTORY_CLEANUP_JOB_DECLARATION

MAX_THREADS_NUMBER

public static final int MAX_THREADS_NUMBER

See Also:

• Constant Field Values

Constructor Details

HistoryCleanupCmd

public HistoryCleanupCmd(boolean immediatelyDue)

Method Details

execute

public Job execute(CommandContext context)

Specified by:

execute in interface Command<Job>

getHistoryCleanupJobs

protected List<Job> getHistoryCleanupJobs()

shouldCreateJobs

protected boolean shouldCreateJobs(List<Job> jobs)

shouldReconfigureJobs

protected boolean shouldReconfigureJobs(List<Job> jobs)

shouldSuspendJobs

protected boolean shouldSuspendJobs(List<Job> jobs)

willBeScheduled

protected boolean willBeScheduled()

createJobs

protected List<Job> createJobs(int[][] minuteChunks)

reconfigureJobs

protected List<Job> reconfigureJobs(List<Job> historyCleanupJobs,
 int degreeOfParallelism,
 int[][] minuteChunks)

suspendJobs

protected void suspendJobs(List<Job> jobs)

createJob

protected JobEntity createJob(int[] minuteChunk,
 int maxRetries)

createCleanupContext

protected HistoryCleanupContext createCleanupContext(int[] minuteChunk,
 int maxRetries)

writeUserOperationLog

protected void writeUserOperationLog(CommandContext commandContext)

acquireExclusiveLock

protected void acquireExclusiveLock(CommandContext commandContext)

isRetryable

public boolean isRetryable()

When CockroachDB is used, this command may be retried multiple times until it is successful, or the retries are exhausted. CockroachDB uses a stricter, SERIALIZABLE transaction isolation which ensures a serialized manner of transaction execution. A concurrent transaction that attempts to modify the same data as another transaction is required to abort, rollback and retry. This also makes our use-case of pessimistic locks redundant since we only use them as synchronization barriers, and not to lock actual data which would protect it from concurrent modifications. The History Cleanup command only executes internal code, so we are certain that a retry of a failed reconfiguraton will not impact user data, and may be performed multiple times.

Specified by:

isRetryable in interface Command<Job>

Returns:

true if the CrdbTransactionRetryInterceptor can make a transparent retry of this command upon failure with a CrdbTransactionRetryException (only used when running on CockroachDB).