edu.umass.cs.reconfiguration.reconfigurationutils

Class DemandProfile

java.lang.Object

edu.umass.cs.reconfiguration.reconfigurationutils.AbstractDemandProfile

edu.umass.cs.reconfiguration.reconfigurationutils.DemandProfile

Direct Known Subclasses:

ProximateBalance

public class DemandProfile
extends AbstractDemandProfile

Author:

V. Arun This sample implementation of AbstractDemandProfile maintains the demand profile for a single name and returns it as a JSONObject via its getStats() method. The specification of its methods is in the documentation of AbstractDemandProfile.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	DemandProfile.Keys

Field Summary

Fields

Modifier and Type	Field and Description
protected double	interArrivalTime
protected DemandProfile	lastReconfiguredProfile
protected long	lastRequestTime
protected static long	minReconfigurationInterval The minimum amount of time (ms) that must elapse since the previous reconfiguration before the next reconfiguration can happen.
protected static int	minRequestsBeforeDemandReport The minimum number of requests after which a demand report will be sent to reconfigurators.
protected static long	minRequestsBeforeReconfiguration The minimum number of requests between two successive reconfigurations.
protected int	numRequests
protected int	numTotalRequests

Fields inherited from class edu.umass.cs.reconfiguration.reconfigurationutils.AbstractDemandProfile

name

Constructor Summary

Constructors

Constructor and Description
DemandProfile(DemandProfile dp) Deep copy constructor.
DemandProfile(org.json.JSONObject json) All AbstractDemandProfile instances must be constructible from a JSONObject.
DemandProfile(java.lang.String name) The string argument name is the service name for which this demand profile is being maintained.

Method Summary

Modifier and Type	Method and Description
void	combine(AbstractDemandProfile dp) Combine the new information in update into this.
static DemandProfile	createDemandProfile(java.lang.String name)
org.json.JSONObject	getDemandStats() All relevant stats must be serializable into JSONObject.
double	getNumRequests()
double	getNumTotalRequests()
double	getRequestRate()
void	justReconfigured() Tells this that the current demand profile was just used to perform reconfiguration.
static void	main(java.lang.String[] args)
java.util.Set<java.lang.String>	reconfigure(java.util.Set<java.lang.String> curActives, ReconfigurableAppInfo nodeConfig) The main reconfiguration policy invoked at reconfigurators (not active replicas).
boolean	shouldReportDemandStats(Request request, java.net.InetAddress sender, ReconfigurableAppInfo nodeConfig) This method is used to inform the reconfiguration policy that request received from a client at IP address sender.

Methods inherited from class edu.umass.cs.reconfiguration.reconfigurationutils.AbstractDemandProfile

clone, createDemandProfile, createDemandProfile, getName, reset

Methods inherited from class java.lang.Object

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

Field Detail

minRequestsBeforeDemandReport

protected static int minRequestsBeforeDemandReport

The minimum number of requests after which a demand report will be sent to reconfigurators.

minReconfigurationInterval

protected static long minReconfigurationInterval

The minimum amount of time (ms) that must elapse since the previous reconfiguration before the next reconfiguration can happen.

minRequestsBeforeReconfiguration

protected static long minRequestsBeforeReconfiguration

The minimum number of requests between two successive reconfigurations.

interArrivalTime

protected double interArrivalTime

lastRequestTime

protected long lastRequestTime

numRequests

protected int numRequests

numTotalRequests

protected int numTotalRequests

lastReconfiguredProfile

protected DemandProfile lastReconfiguredProfile

Constructor Detail

DemandProfile

public DemandProfile(java.lang.String name)

The string argument name is the service name for which this demand profile is being maintained.

Parameters:

name -

DemandProfile

public DemandProfile(DemandProfile dp)

Deep copy constructor. This constructor should create a copy of the supplied DemandProfile argument dp such that the newly constructed DemandProfile instance dpCopy != dp but dpCopy.equals(dp).

Parameters:

dp -

DemandProfile

public DemandProfile(org.json.JSONObject json)
              throws org.json.JSONException

All AbstractDemandProfile instances must be constructible from a JSONObject.

Parameters:

json -

Throws:

org.json.JSONException

Method Detail

createDemandProfile

public static DemandProfile createDemandProfile(java.lang.String name)

Parameters:

name -

Returns:

All AbstractDemandProfile instances must support a single String argument constructor that is the underlying service name.

shouldReportDemandStats

public boolean shouldReportDemandStats(Request request,
                                       java.net.InetAddress sender,
                                       ReconfigurableAppInfo nodeConfig)

This method is used to inform the reconfiguration policy that request received from a client at IP address sender. The parameter nodeConfig provides the list of all active replica locations. The reconfiguration policy may use this information to assimilate a demand distribution and use that to determine whether and how to reconfigure the current set of replicas. The simplistic example below ignores the sender information that in general is needed to determine the geo-distribution of demand.

Specified by:

shouldReportDemandStats in class AbstractDemandProfile

Returns:

Whether the active replica should send a demand report to the reconfigurator.

getRequestRate

public double getRequestRate()

Returns:

Request rate for the service name.

getNumRequests

public double getNumRequests()

Returns:

Number of requests for this service name since the most recent demand report was sent to reconfigurators.

getNumTotalRequests

public double getNumTotalRequests()

Returns:

Total number of requests for this service name.

getDemandStats

public org.json.JSONObject getDemandStats()

Description copied from class: AbstractDemandProfile

All relevant stats must be serializable into JSONObject. Any information not included in the returned JSONObject will not be available for use in the reconfiguration policy in AbstractDemandProfile.reconfigure(Set, ReconfigurableAppInfo) that is invoked at reconfigurators (not active replicas).

Specified by:

getDemandStats in class AbstractDemandProfile

Returns:

Demand statistics as JSON.

combine

public void combine(AbstractDemandProfile dp)

Description copied from class: AbstractDemandProfile

Combine the new information in update into this. This method is used at reconfigurators to combine a newly received demand report with an existing demand report.

Specified by:

combine in class AbstractDemandProfile

reconfigure

public java.util.Set<java.lang.String> reconfigure(java.util.Set<java.lang.String> curActives,
                                                   ReconfigurableAppInfo nodeConfig)

Description copied from class: AbstractDemandProfile

The main reconfiguration policy invoked at reconfigurators (not active replicas).

Specified by:

reconfigure in class AbstractDemandProfile

Returns:

The list of reconfigured actives for the new placement. Simply returning null means no reconfiguration will happen. Returning a list that is the same as curActives means that a trivial reconfiguration will happen unless ReconfigurationConfig.RC.RECONFIGURE_IN_PLACE is set to false.

justReconfigured

public void justReconfigured()

Description copied from class: AbstractDemandProfile

Tells this that the current demand profile was just used to perform reconfiguration. This information is useful for implementing policies based on the difference between the current demand profile and the one at the time of the most recent reconfiguration, e.g., reconfigure only if the demand from some region has changed by more than 10%.

Specified by:

justReconfigured in class AbstractDemandProfile

main

public static void main(java.lang.String[] args)

Parameters:

args -