ostore.archive
Class GenerateChkptStage

java.lang.Object
  |
  +--ostore.archive.GenerateChkptStage

All Implemented Interfaces:

EventHandlerIF, ProfilableIF, SingleThreadedEventHandlerIF

public class GenerateChkptStage

extends Object

implements SingleThreadedEventHandlerIF, EventHandlerIF, ProfilableIF

The GenerateChkptStage generates a checkpoint for a particular version. The result is a V-GUID or version GUID.

The GenerateChkptStage creates a checkpoint by sending a GenerateFragsBlkReq for each uniquely modified VerifiableBlock. When the checkpointing process is done, all uniquely modified VerifiableBlocks have been Erasure encoded into n Fragments and a BucketsToDisseminateEvent containing the resulting GUID's of all the uniquely modified VerifiableBlocks has been dispatched.

USAGE

To create a checkpoint dispatch a GenerateFragsChkptReq containing the CacheableIdentity (i.e. VHASH) of the top VerifiableBlock, the number of Fragments to Erasure encode, the inverse rate of encoding, and the Erasure code type. The local GenerateChkptStage will receive the checkpoint request message and return a GenerateFragsChkptResp that either includes the resulting V-GUID.

INITIALIZATION PARAMETERS

node_id

NodeId of the local server where this stage is running.

AlarmTimeout

Period to timeout (in milliseconds)

Version:

$Id: GenerateChkptStage.java,v 1.56 2004/05/13 20:13:06 hweather Exp $

Author:

Hakim Weatherspoon

See Also:

GenerateFragsBlkReq, GenerateFragsBlkResp, GenerateFragsChkptReq, GenerateFragsChkptResp, BucketsToDisseminateEvent, Erasure, Disseminatable, Fragment, VerifiableBlock, DataObject, Btree.InteriorNode, DataObject.DataBlock

Constructor Summary

GenerateChkptStage()

Method Summary

void	destroy()
void	handleEvent(QueueElementIF item)
void	handleEvents(QueueElementIF[] items)
void	init(ConfigDataIF config)
int	profileSize()

Methods inherited from class java.lang.Object

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

Constructor Detail

GenerateChkptStage

public GenerateChkptStage()

Method Detail

handleEvent

public void handleEvent(QueueElementIF item)
                 throws EventHandlerException

Specified by:

handleEvent in interface EventHandlerIF

EventHandlerException

handleEvents

public void handleEvents(QueueElementIF[] items)
                  throws EventHandlerException

Specified by:

handleEvents in interface EventHandlerIF

EventHandlerException

init

public void init(ConfigDataIF config)
          throws Exception

Specified by:

init in interface EventHandlerIF

Exception

destroy

public void destroy()
             throws Exception

Specified by:

destroy in interface EventHandlerIF

Exception

profileSize

public int profileSize()

Specified by:

profileSize in interface ProfilableIF