com.bigdata.rdf.sail.webapp.lbs

Class HostScore

java.lang.Object

com.bigdata.rdf.sail.webapp.lbs.HostScore

public class HostScore
extends Object

Helper class pairs a hostname and the normalized availabilty for that host. The availability is based on (normalized) 1 - LOAD for the host. The LOAD is computed using the IHostMetrics and an IHostScoringRule for computing the workload of a host from those metrics. The availability is then computed from the LOAD and normalized.

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
static Comparator<HostScore>	COMPARE_BY_HOSTNAME Orders by hostname.
static Comparator<HostScore>	COMPARE_BY_SCORE Places elements into order by decreasing normalized load.

Constructor Summary

Constructors

Constructor and Description
HostScore(String hostname, double availability)

Method Summary

Methods

Modifier and Type	Method and Description
double	getAvailability() Return the normalized availability for the host.
String	getHostname() Return the hostname.
boolean	isThisHost() Return true iff the host is this host.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

COMPARE_BY_SCORE

public static final Comparator<HostScore> COMPARE_BY_SCORE

Places elements into order by decreasing normalized load. The getHostname() is used to break any ties.

COMPARE_BY_HOSTNAME

public static final Comparator<HostScore> COMPARE_BY_HOSTNAME

Orders by hostname. This provides a stable way of viewing the data in /bigdata/status.

Constructor Detail

HostScore

public HostScore(String hostname,
         double availability)

Parameters:

hostname - The hostname (required, must be non-empty).

availability - The normalized availability score for this host.

Method Detail

getAvailability

public double getAvailability()

Return the normalized availability for the host. Load balancing decision are based on this normalized score (work is assigned to hosts in inverse proportion to the normalized load of the host).

getHostname

public String getHostname()

Return the hostname.

isThisHost

public boolean isThisHost()

Return true iff the host is this host.

toString

public String toString()

Overrides:

toString in class Object