org.apache.hadoop.yarn.api.resource

Class PlacementConstraints

java.lang.Object

org.apache.hadoop.yarn.api.resource.PlacementConstraints

@InterfaceAudience.Public
 @InterfaceStability.Unstable
public final class PlacementConstraints
extends Object

This class contains various static methods for the applications to create placement constraints (see also PlacementConstraint).

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	PlacementConstraints.PlacementTargets Class with static methods for constructing target expressions to be used in placement constraints.

Field Summary

Fields

Modifier and Type	Field and Description
static String	NODE
static String	NODE_PARTITION
static String	RACK

Method Summary

Modifier and Type	Method and Description
static PlacementConstraint.And	and(PlacementConstraint.AbstractConstraint... children) A conjunction of constraints.
static PlacementConstraint	build(PlacementConstraint.AbstractConstraint constraintExpr) Creates a PlacementConstraint given a constraint expression.
static PlacementConstraint.AbstractConstraint	cardinality(String scope, int minCardinality, int maxCardinality, String... allocationTags) Creates a constraint that restricts the number of allocations within a given scope (e.g., node or rack).
static PlacementConstraint.AbstractConstraint	cardinality(String scope, String namespace, int minCardinality, int maxCardinality, String... allocationTags) Similar to cardinality(String, int, int, String...), but let you attach a namespace to the given allocation tags.
static PlacementConstraint.DelayedOr	delayedOr(PlacementConstraint.TimedPlacementConstraint... children) Creates a composite constraint that includes a list of timed placement constraints.
static PlacementConstraint.AbstractConstraint	maxCardinality(String scope, int maxCardinality, String... allocationTags) Similar to cardinality(String, int, int, String...), but determines only the maximum cardinality (the minimum cardinality is 0).
static PlacementConstraint.AbstractConstraint	maxCardinality(String scope, String tagNamespace, int maxCardinality, String... allocationTags) Similar to maxCardinality(String, int, String...), but let you specify a namespace for the tags, see supported namespaces in AllocationTagNamespaceType.
static PlacementConstraint.AbstractConstraint	minCardinality(String scope, int minCardinality, String... allocationTags) Similar to cardinality(String, int, int, String...), but determines only the minimum cardinality (the maximum cardinality is unbound).
static PlacementConstraint.AbstractConstraint	minCardinality(String scope, String namespace, int minCardinality, String... allocationTags) Similar to minCardinality(String, int, String...), but let you attach a namespace to the allocation tags.
static PlacementConstraint.Or	or(PlacementConstraint.AbstractConstraint... children) A disjunction of constraints.
static PlacementConstraint.AbstractConstraint	targetCardinality(String scope, int minCardinality, int maxCardinality, PlacementConstraint.TargetExpression... targetExpressions) This constraint generalizes the cardinality and target constraints.
static PlacementConstraint.AbstractConstraint	targetIn(String scope, PlacementConstraint.TargetExpression... targetExpressions) Creates a constraint that requires allocations to be placed on nodes that satisfy all target expressions within the given scope (e.g., node or rack).
static PlacementConstraint.AbstractConstraint	targetNodeAttribute(String scope, NodeAttributeOpCode opCode, PlacementConstraint.TargetExpression... targetExpressions) Creates a constraint that requires allocations to be placed on nodes that belong to a scope (e.g., node or rack) that satisfy any of the target expressions based on node attribute op code.
static PlacementConstraint.AbstractConstraint	targetNotIn(String scope, PlacementConstraint.TargetExpression... targetExpressions) Creates a constraint that requires allocations to be placed on nodes that belong to a scope (e.g., node or rack) that does not satisfy any of the target expressions.
static PlacementConstraint.TimedPlacementConstraint	timedClockConstraint(PlacementConstraint.AbstractConstraint constraint, long delay, TimeUnit timeUnit) Creates a placement constraint that has to be satisfied within a time window.
static PlacementConstraint.TimedPlacementConstraint	timedOpportunitiesConstraint(PlacementConstraint.AbstractConstraint constraint, long delay) Creates a placement constraint that has to be satisfied within a number of placement opportunities (invocations of the scheduler).

Methods inherited from class java.lang.Object

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

Field Detail

NODE

public static final String NODE

See Also:

Constant Field Values

RACK

public static final String RACK

See Also:

Constant Field Values

NODE_PARTITION

public static final String NODE_PARTITION

See Also:

Constant Field Values

Method Detail

targetIn

public static PlacementConstraint.AbstractConstraint targetIn(String scope,
                                                              PlacementConstraint.TargetExpression... targetExpressions)

Creates a constraint that requires allocations to be placed on nodes that satisfy all target expressions within the given scope (e.g., node or rack). For example, targetIn(RACK, allocationTag("hbase-m")), allows allocations on nodes that belong to a rack that has at least one tag with value "hbase-m".

Parameters:

scope - the scope within which the target expressions should be satisfied

targetExpressions - the expressions that need to be satisfied within the scope

Returns:

the resulting placement constraint

targetNotIn

public static PlacementConstraint.AbstractConstraint targetNotIn(String scope,
                                                                 PlacementConstraint.TargetExpression... targetExpressions)

Creates a constraint that requires allocations to be placed on nodes that belong to a scope (e.g., node or rack) that does not satisfy any of the target expressions.

Parameters:

scope - the scope within which the target expressions should not be true

targetExpressions - the expressions that need to not be true within the scope

Returns:

the resulting placement constraint

targetNodeAttribute

public static PlacementConstraint.AbstractConstraint targetNodeAttribute(String scope,
                                                                         NodeAttributeOpCode opCode,
                                                                         PlacementConstraint.TargetExpression... targetExpressions)

Creates a constraint that requires allocations to be placed on nodes that belong to a scope (e.g., node or rack) that satisfy any of the target expressions based on node attribute op code.

Parameters:

scope - the scope within which the target expressions should not be true

opCode - Node Attribute code which could be equals, not equals.

targetExpressions - the expressions that need to not be true within the scope

Returns:

the resulting placement constraint

cardinality

public static PlacementConstraint.AbstractConstraint cardinality(String scope,
                                                                 int minCardinality,
                                                                 int maxCardinality,
                                                                 String... allocationTags)

Creates a constraint that restricts the number of allocations within a given scope (e.g., node or rack). For example, cardinality(NODE, 3, 10, "zk") is satisfied on nodes where there are no less than 3 allocations with tag "zk" and no more than 10.

Parameters:

scope - the scope of the constraint

minCardinality - determines the minimum number of allocations within the scope

maxCardinality - determines the maximum number of allocations within the scope

allocationTags - the constraint targets allocations with these tags

Returns:

the resulting placement constraint

cardinality

public static PlacementConstraint.AbstractConstraint cardinality(String scope,
                                                                 String namespace,
                                                                 int minCardinality,
                                                                 int maxCardinality,
                                                                 String... allocationTags)

Similar to cardinality(String, int, int, String...), but let you attach a namespace to the given allocation tags.

Parameters:

scope - the scope of the constraint

namespace - the namespace of the allocation tags

minCardinality - determines the minimum number of allocations within the scope

maxCardinality - determines the maximum number of allocations within the scope

allocationTags - allocation tags

Returns:

the resulting placement constraint

minCardinality

public static PlacementConstraint.AbstractConstraint minCardinality(String scope,
                                                                    int minCardinality,
                                                                    String... allocationTags)

Similar to cardinality(String, int, int, String...), but determines only the minimum cardinality (the maximum cardinality is unbound).

Parameters:

scope - the scope of the constraint

minCardinality - determines the minimum number of allocations within the scope

allocationTags - the constraint targets allocations with these tags

Returns:

the resulting placement constraint

minCardinality

public static PlacementConstraint.AbstractConstraint minCardinality(String scope,
                                                                    String namespace,
                                                                    int minCardinality,
                                                                    String... allocationTags)

Similar to minCardinality(String, int, String...), but let you attach a namespace to the allocation tags.

Parameters:

scope - the scope of the constraint

namespace - the namespace of these tags

minCardinality - determines the minimum number of allocations within the scope

allocationTags - the constraint targets allocations with these tags

Returns:

the resulting placement constraint

maxCardinality

public static PlacementConstraint.AbstractConstraint maxCardinality(String scope,
                                                                    int maxCardinality,
                                                                    String... allocationTags)

Similar to cardinality(String, int, int, String...), but determines only the maximum cardinality (the minimum cardinality is 0).

Parameters:

scope - the scope of the constraint

maxCardinality - determines the maximum number of allocations within the scope

allocationTags - the constraint targets allocations with these tags

Returns:

the resulting placement constraint

maxCardinality

public static PlacementConstraint.AbstractConstraint maxCardinality(String scope,
                                                                    String tagNamespace,
                                                                    int maxCardinality,
                                                                    String... allocationTags)

Similar to maxCardinality(String, int, String...), but let you specify a namespace for the tags, see supported namespaces in AllocationTagNamespaceType.

Parameters:

scope - the scope of the constraint

tagNamespace - the namespace of these tags

maxCardinality - determines the maximum number of allocations within the scope

allocationTags - allocation tags

Returns:

the resulting placement constraint

targetCardinality

public static PlacementConstraint.AbstractConstraint targetCardinality(String scope,
                                                                       int minCardinality,
                                                                       int maxCardinality,
                                                                       PlacementConstraint.TargetExpression... targetExpressions)

This constraint generalizes the cardinality and target constraints. Consider a set of nodes N that belongs to the scope specified in the constraint. If the target expressions are satisfied at least minCardinality times and at most maxCardinality times in the node set N, then the constraint is satisfied. For example, targetCardinality(RACK, 2, 10, allocationTag("zk")), requires an allocation to be placed within a rack that has at least 2 and at most 10 other allocations with tag "zk".

Parameters:

scope - the scope of the constraint

minCardinality - the minimum number of times the target expressions have to be satisfied with the given scope

maxCardinality - the maximum number of times the target expressions have to be satisfied with the given scope

targetExpressions - the target expressions

Returns:

the resulting placement constraint

and

public static PlacementConstraint.And and(PlacementConstraint.AbstractConstraint... children)

A conjunction of constraints.

Parameters:

children - the children constraints that should all be satisfied

Returns:

the resulting placement constraint

or

public static PlacementConstraint.Or or(PlacementConstraint.AbstractConstraint... children)

A disjunction of constraints.

Parameters:

children - the children constraints, one of which should be satisfied

Returns:

the resulting placement constraint

delayedOr

public static PlacementConstraint.DelayedOr delayedOr(PlacementConstraint.TimedPlacementConstraint... children)

Creates a composite constraint that includes a list of timed placement constraints. The scheduler should try to satisfy first the first timed child constraint within the specified time window. If this is not possible, it should attempt to satisfy the second, and so on.

Parameters:

children - the timed children constraints

Returns:

the resulting composite constraint

timedClockConstraint

public static PlacementConstraint.TimedPlacementConstraint timedClockConstraint(PlacementConstraint.AbstractConstraint constraint,
                                                                                long delay,
                                                                                TimeUnit timeUnit)

Creates a placement constraint that has to be satisfied within a time window.

Parameters:

constraint - the placement constraint

delay - the length of the time window within which the constraint has to be satisfied

timeUnit - the unit of time of the time window

Returns:

the resulting timed placement constraint

timedOpportunitiesConstraint

public static PlacementConstraint.TimedPlacementConstraint timedOpportunitiesConstraint(PlacementConstraint.AbstractConstraint constraint,
                                                                                        long delay)

Creates a placement constraint that has to be satisfied within a number of placement opportunities (invocations of the scheduler).

Parameters:

constraint - the placement constraint

delay - the number of scheduling opportunities within which the constraint has to be satisfied

Returns:

the resulting timed placement constraint

build

public static PlacementConstraint build(PlacementConstraint.AbstractConstraint constraintExpr)

Creates a PlacementConstraint given a constraint expression.

Parameters:

constraintExpr - the constraint expression

Returns:

the placement constraint