org.apache.hadoop.hbase.ipc

Class SimpleRpcScheduler

java.lang.Object

org.apache.hadoop.hbase.ipc.RpcScheduler

org.apache.hadoop.hbase.ipc.SimpleRpcScheduler

All Implemented Interfaces:

ConfigurationObserver

public class SimpleRpcScheduler
extends RpcScheduler
implements ConfigurationObserver

The default scheduler. Configurable. Maintains isolated handler pools for general ('default'), high-priority ('priority'), and replication ('replication') requests. Default behavior is to balance the requests across handlers. Add configs to enable balancing by read vs writes, etc. See below article for explanation of options.

See Also:

Overview on Request Queuing

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.ipc.RpcScheduler

RpcScheduler.Context

Field Summary

Fields inherited from class org.apache.hadoop.hbase.ipc.RpcScheduler

IPC_SERVER_MAX_CALLQUEUE_LENGTH, IPC_SERVER_PRIORITY_MAX_CALLQUEUE_LENGTH

Constructor Summary

Constructors

Constructor and Description
SimpleRpcScheduler(Configuration conf, int handlerCount, int priorityHandlerCount, int replicationHandlerCount, PriorityFunction priority, Abortable server, int highPriorityLevel)
SimpleRpcScheduler(Configuration conf, int handlerCount, int priorityHandlerCount, int replicationHandlerCount, PriorityFunction priority, int highPriorityLevel)

Method Summary

Modifier and Type	Method and Description
boolean	dispatch(CallRunner callTask) Dispatches an RPC request asynchronously.
int	getActiveReadRpcHandlerCount() Retrieves the number of active write rpc handler when use RWQueueRpcExecutor.
int	getActiveRpcHandlerCount() Retrieves the number of active handler.
int	getActiveScanRpcHandlerCount() Retrieves the number of active write rpc handler when use RWQueueRpcExecutor.
int	getActiveWriteRpcHandlerCount() Retrieves the number of active write rpc handler when use RWQueueRpcExecutor.
CallQueueInfo	getCallQueueInfo() Get call queue information
int	getGeneralQueueLength() Retrieves length of the general queue for metrics.
long	getNumGeneralCallsDropped() If CoDel-based RPC executors are used, retrieves the number of Calls that were dropped from general queue because RPC executor is under high load; returns 0 otherwise.
long	getNumLifoModeSwitches() If CoDel-based RPC executors are used, retrieves the number of Calls that were picked from the tail of the queue (indicating adaptive LIFO mode, when in the period of overloade we serve last requests first); returns 0 otherwise.
int	getPriorityQueueLength() Retrieves length of the priority queue for metrics.
int	getReadQueueLength() Retrieves length of the read queue for metrics when use RWQueueRpcExecutor.
int	getReplicationQueueLength() Retrieves length of the replication queue for metrics.
int	getScanQueueLength() Retrieves length of the scan queue for metrics when use RWQueueRpcExecutor.
int	getWriteQueueLength() Retrieves length of the write queue for metrics when use RWQueueRpcExecutor.
void	init(RpcScheduler.Context context) Does some quick initialization.
void	onConfigurationChange(Configuration conf) Resize call queues;
void	start() Prepares for request serving.
void	stop() Stops serving new requests.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleRpcScheduler

public SimpleRpcScheduler(Configuration conf,
                          int handlerCount,
                          int priorityHandlerCount,
                          int replicationHandlerCount,
                          PriorityFunction priority,
                          Abortable server,
                          int highPriorityLevel)

Parameters:

conf -

handlerCount - the number of handler threads that will be used to process calls

priorityHandlerCount - How many threads for priority handling.

replicationHandlerCount - How many threads for replication handling.

highPriorityLevel -

priority - Function to extract request priority.

SimpleRpcScheduler

public SimpleRpcScheduler(Configuration conf,
                          int handlerCount,
                          int priorityHandlerCount,
                          int replicationHandlerCount,
                          PriorityFunction priority,
                          int highPriorityLevel)

Method Detail

onConfigurationChange

public void onConfigurationChange(Configuration conf)

Resize call queues;

Specified by:

onConfigurationChange in interface ConfigurationObserver

Parameters:

conf - new configuration

init

public void init(RpcScheduler.Context context)

Description copied from class: RpcScheduler

Does some quick initialization. Heavy tasks (e.g. starting threads) should be done in RpcScheduler.start(). This method is called before start.

Specified by:

init in class RpcScheduler

Parameters:

context - provides methods to retrieve runtime information from

start

public void start()

Description copied from class: RpcScheduler

Prepares for request serving. An implementation may start some handler threads here.

Specified by:

start in class RpcScheduler

stop

public void stop()

Description copied from class: RpcScheduler

Stops serving new requests.

Specified by:

stop in class RpcScheduler

dispatch

public boolean dispatch(CallRunner callTask)
                 throws java.lang.InterruptedException

Description copied from class: RpcScheduler

Dispatches an RPC request asynchronously. An implementation is free to choose to process the request immediately or delay it for later processing.

Specified by:

dispatch in class RpcScheduler

Parameters:

callTask - the request to be dispatched

Throws:

java.lang.InterruptedException

getGeneralQueueLength

public int getGeneralQueueLength()

Description copied from class: RpcScheduler

Retrieves length of the general queue for metrics.

Specified by:

getGeneralQueueLength in class RpcScheduler

getPriorityQueueLength

public int getPriorityQueueLength()

Description copied from class: RpcScheduler

Retrieves length of the priority queue for metrics.

Specified by:

getPriorityQueueLength in class RpcScheduler

getReplicationQueueLength

public int getReplicationQueueLength()

Description copied from class: RpcScheduler

Retrieves length of the replication queue for metrics.

Specified by:

getReplicationQueueLength in class RpcScheduler

getActiveRpcHandlerCount

public int getActiveRpcHandlerCount()

Description copied from class: RpcScheduler

Retrieves the number of active handler.

Specified by:

getActiveRpcHandlerCount in class RpcScheduler

getNumGeneralCallsDropped

public long getNumGeneralCallsDropped()

Description copied from class: RpcScheduler

If CoDel-based RPC executors are used, retrieves the number of Calls that were dropped from general queue because RPC executor is under high load; returns 0 otherwise.

Specified by:

getNumGeneralCallsDropped in class RpcScheduler

getNumLifoModeSwitches

public long getNumLifoModeSwitches()

Description copied from class: RpcScheduler

If CoDel-based RPC executors are used, retrieves the number of Calls that were picked from the tail of the queue (indicating adaptive LIFO mode, when in the period of overloade we serve last requests first); returns 0 otherwise.

Specified by:

getNumLifoModeSwitches in class RpcScheduler

getWriteQueueLength

public int getWriteQueueLength()

Description copied from class: RpcScheduler

Retrieves length of the write queue for metrics when use RWQueueRpcExecutor.

Specified by:

getWriteQueueLength in class RpcScheduler

getReadQueueLength

public int getReadQueueLength()

Description copied from class: RpcScheduler

Retrieves length of the read queue for metrics when use RWQueueRpcExecutor.

Specified by:

getReadQueueLength in class RpcScheduler

getScanQueueLength

public int getScanQueueLength()

Description copied from class: RpcScheduler

Retrieves length of the scan queue for metrics when use RWQueueRpcExecutor.

Specified by:

getScanQueueLength in class RpcScheduler

getActiveWriteRpcHandlerCount

public int getActiveWriteRpcHandlerCount()

Description copied from class: RpcScheduler

Retrieves the number of active write rpc handler when use RWQueueRpcExecutor.

Specified by:

getActiveWriteRpcHandlerCount in class RpcScheduler

getActiveReadRpcHandlerCount

public int getActiveReadRpcHandlerCount()

Description copied from class: RpcScheduler

Retrieves the number of active write rpc handler when use RWQueueRpcExecutor.

Specified by:

getActiveReadRpcHandlerCount in class RpcScheduler

getActiveScanRpcHandlerCount

public int getActiveScanRpcHandlerCount()

Description copied from class: RpcScheduler

Retrieves the number of active write rpc handler when use RWQueueRpcExecutor.

Specified by:

getActiveScanRpcHandlerCount in class RpcScheduler

getCallQueueInfo

public CallQueueInfo getCallQueueInfo()

Description copied from class: RpcScheduler

Get call queue information

Specified by:

getCallQueueInfo in class RpcScheduler