com.bigdata.concurrent

Class NonBlockingLockManager.Counters

java.lang.Object

com.bigdata.concurrent.NonBlockingLockManager.Counters

Enclosing class:

NonBlockingLockManager<R extends Comparable<R>>

protected static class NonBlockingLockManager.Counters
extends Object

Counters for the NonBlockingLockManager.

Version:

$Id$

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
int	maxRunning The maximum observed value of nrunning.
long	naccepted The #of tasks that were accepted by the service (running total).
long	ncancel The #of tasks that were cancelled (running total).
long	ndeadlock The #of tasks that deadlocked when they attempted to acquire their locks (running total).
long	nended The #of tasks that whose execution on the delegate Executor is complete (either by normal completion or by error, but only for tasks which were executed on the delegate) (running total).
long	nerror The #of tasks whose exception was set (running total).
long	nrejected The #of tasks that were rejected by the service (running total).
int	nrunning #of tasks that have acquired their locks and are concurrently executing.
long	nstarted The #of tasks that have been started on the delegate Executor (running total).
long	ntimeout The #of tasks that timed out when they attempted to acquire their locks (running total).
int	nwaiting #of tasks that are currently waiting on locks.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	NonBlockingLockManager.Counters()

Method Summary

Methods inherited from class java.lang.Object

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

Field Detail

naccepted

public long naccepted

The #of tasks that were accepted by the service (running total).

nrejected

public long nrejected

The #of tasks that were rejected by the service (running total).

nstarted

public long nstarted

The #of tasks that have been started on the delegate Executor (running total).

nended

public long nended

The #of tasks that whose execution on the delegate Executor is complete (either by normal completion or by error, but only for tasks which were executed on the delegate) (running total).

ncancel

public long ncancel

The #of tasks that were cancelled (running total).

nerror

public long nerror

The #of tasks whose exception was set (running total).

ndeadlock

public long ndeadlock

The #of tasks that deadlocked when they attempted to acquire their locks (running total). Note that a task MAY retry lock acquisition and this counter will be incremented each time it does so and then deadlocks.

ntimeout

public long ntimeout

The #of tasks that timed out when they attempted to acquire their locks (running total). Note that a task MAY retry lock acquisition and this counter will be incremented each time it does so and then times out.

nwaiting

public int nwaiting

#of tasks that are currently waiting on locks. This is the effective queue length of the NonBlockingLockManager. To get the actual queue length you need to add this to the length of the queue for the delegate Executor. FIXME This counter can be off since a task does not "know" when it is placed onto the [waitingTasks] queue and therefore can not decrement the counter conditionally if the task is cancelled or if an exception is set. Right now the counter is only decremented if the task begins to execute. This is a problem since this is the primary indication of the total size of the NonBlockingLockManager as a queue feeding its delegate Executor.

nrunning

public int nrunning

#of tasks that have acquired their locks and are concurrently executing. This is the true measure of concurrency.

maxRunning

public int maxRunning

The maximum observed value of nrunning.

Constructor Detail

NonBlockingLockManager.Counters

protected NonBlockingLockManager.Counters()