backtype.storm.scheduler.multitenant

Class NodePool

java.lang.Object

backtype.storm.scheduler.multitenant.NodePool

Direct Known Subclasses:

DefaultPool, FreePool, IsolatedPool

public abstract class NodePool
extends Object

A pool of nodes that can be used to run topologies.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	NodePool.NodeAndSlotCounts
static class	NodePool.RoundRobinSlotScheduler Place executors into slots in a round robin way, taking into account component spreading among different hosts.

Field Summary

Fields

Modifier and Type	Field and Description
protected Cluster	_cluster
protected Map<String,Node>	_nodeIdToNode

Constructor Summary

Constructors

Constructor and Description
NodePool()

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	addTopology(TopologyDetails td) Add a topology to the pool
abstract boolean	canAdd(TopologyDetails td) Check if this topology can be added to this pool
abstract NodePool.NodeAndSlotCounts	getNodeAndSlotCountIfSlotsWereTaken(int slots) Get the number of nodes and slots this would provide to get the slots needed
static int	getNodeCountIfSlotsWereTaken(int slots, NodePool[] pools)
void	init(Cluster cluster, Map<String,Node> nodeIdToNode) Initialize the pool.
abstract int	nodesAvailable()
static int	nodesAvailable(NodePool[] pools)
abstract void	scheduleAsNeeded(NodePool... lesserPools) Reschedule any topologies as needed.
abstract int	slotsAvailable()
static int	slotsAvailable(NodePool[] pools)
abstract Collection<Node>	takeNodes(int nodesNeeded) Take up to nodesNeeded from this pool
static Collection<Node>	takeNodes(int nodesNeeded, NodePool[] pools)
static Collection<Node>	takeNodesBySlot(int slotsNeeded, NodePool[] pools)
abstract Collection<Node>	takeNodesBySlots(int slotsNeeded) Take nodes from this pool that can fulfill possibly up to the slotsNeeded

Methods inherited from class java.lang.Object

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

Field Detail

_cluster

protected Cluster _cluster

_nodeIdToNode

protected Map<String,Node> _nodeIdToNode

Constructor Detail

NodePool

public NodePool()

Method Detail

init

public void init(Cluster cluster,
        Map<String,Node> nodeIdToNode)

Initialize the pool.

Parameters:

cluster - the cluster

nodeIdToNode - the mapping of node id to nodes

addTopology

public abstract void addTopology(TopologyDetails td)

Add a topology to the pool

Parameters:

td - the topology to add.

canAdd

public abstract boolean canAdd(TopologyDetails td)

Check if this topology can be added to this pool

Parameters:

td - the topology

Returns:

true if it can else false

slotsAvailable

public abstract int slotsAvailable()

Returns:

the number of nodes that are available to be taken

takeNodesBySlots

public abstract Collection<Node> takeNodesBySlots(int slotsNeeded)

Take nodes from this pool that can fulfill possibly up to the slotsNeeded

Parameters:

slotsNeeded - the number of slots that are needed.

Returns:

a Collection of nodes with the removed nodes in it. This may be empty, but should not be null.

getNodeAndSlotCountIfSlotsWereTaken

public abstract NodePool.NodeAndSlotCounts getNodeAndSlotCountIfSlotsWereTaken(int slots)

Get the number of nodes and slots this would provide to get the slots needed

Parameters:

slots - the number of slots needed

Returns:

the number of nodes and slots that would be returned.

nodesAvailable

public abstract int nodesAvailable()

Returns:

the number of nodes that are available to be taken

takeNodes

public abstract Collection<Node> takeNodes(int nodesNeeded)

Take up to nodesNeeded from this pool

Parameters:

nodesNeeded - the number of nodes that are needed.

Returns:

a Collection of nodes with the removed nodes in it. This may be empty, but should not be null.

scheduleAsNeeded

public abstract void scheduleAsNeeded(NodePool... lesserPools)

Reschedule any topologies as needed.

Parameters:

lesserPools - pools that may be used to steal nodes from.

slotsAvailable

public static int slotsAvailable(NodePool[] pools)

nodesAvailable

public static int nodesAvailable(NodePool[] pools)

takeNodesBySlot

public static Collection<Node> takeNodesBySlot(int slotsNeeded,
                               NodePool[] pools)

takeNodes

public static Collection<Node> takeNodes(int nodesNeeded,
                         NodePool[] pools)

getNodeCountIfSlotsWereTaken

public static int getNodeCountIfSlotsWereTaken(int slots,
                               NodePool[] pools)