org.apache.hadoop.hbase.ipc

Class FifoRpcScheduler

java.lang.Object

org.apache.hadoop.hbase.ipc.RpcScheduler

org.apache.hadoop.hbase.ipc.FifoRpcScheduler

public class FifoRpcScheduler
extends RpcScheduler

A very simple RpcScheduler} that serves incoming requests in order. This can be used for HMaster, where no prioritization is needed.

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
FifoRpcScheduler(Configuration conf, int handlerCount)

Method Summary

Modifier and Type	Method and Description
boolean	dispatch(CallRunner task) Dispatches an RPC request asynchronously.
int	getActiveRpcHandlerCount() Retrieves the number of active handler.
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	getReplicationQueueLength() Retrieves length of the replication queue for metrics.
void	init(RpcScheduler.Context context) Does some quick initialization.
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

FifoRpcScheduler

public FifoRpcScheduler(Configuration conf,
                        int handlerCount)

Method Detail

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 task)
                 throws IOException,
                        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:

task - the request to be dispatched

Throws:

IOException

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