DataWriterResourceLimitsQosPolicy Class Reference
[DATA_WRITER_RESOURCE_LIMITS]

Various settings that configure how a com.rti.dds.publication.DataWriter allocates and uses physical memory for internal resources. More...

Inheritance diagram for DataWriterResourceLimitsQosPolicy:

List of all members.

Public Attributes
int	initial_concurrent_blocking_threads
	The initial number of threads that are allowed to concurrently block on write call on the same com.rti.dds.publication.DataWriter.
int	max_concurrent_blocking_threads
	The maximum number of threads that are allowed to concurrently block on write call on the same com.rti.dds.publication.DataWriter.
int	max_remote_reader_filters
	The maximum number of remote readers for which the writer will perform content-based filtering.
int	max_batches
	Represents the maximum number of batches a com.rti.dds.publication.DataWriter will manage.
int	initial_batches
	Represents the initial number of batches a com.rti.dds.publication.DataWriter will manage.
int	cookie_max_length
	Represents the maximum length in bytes of a com.rti.dds.infrastructure.Cookie_t.
boolean	replace_empty_instances
	Whether or not to replace empty instances during instance replacement.
boolean	autoregister_instances
	Whether or not to automatically register new instances.
int	initial_virtual_writers
	The initial number of virtual writers supported by a com.rti.dds.publication.DataWriter.
int	max_virtual_writers
	The maximum number of virtual writers supported by a com.rti.dds.publication.DataWriter.

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Detailed Description

Various settings that configure how a com.rti.dds.publication.DataWriter allocates and uses physical memory for internal resources.

DataWriters must allocate internal structures to handle the simultaneously blocking of threads trying to call com.rti.dds.topic.example.FooDataWriter.write on the same com.rti.dds.publication.DataWriter, for the storage used to batch small samples, and for content-based filters specified by DataReaders.

Most of these internal structures start at an initial size and, by default, will be grown as needed by dynamically allocating additional memory. You may set fixed, maximum sizes for these internal structures if you want to bound the amount of memory that can be used by a com.rti.dds.publication.DataWriter. By setting the initial size to the maximum size, you will prevent RTI Connext from dynamically allocating any memory after the creation of the com.rti.dds.publication.DataWriter.

This QoS policy is an extension to the DDS standard.

Entity:

com.rti.dds.publication.DataWriter

Properties:

RxO = N/A
Changeable = NO

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Member Data Documentation

int initial_concurrent_blocking_threads

The initial number of threads that are allowed to concurrently block on write call on the same com.rti.dds.publication.DataWriter.

This value only applies if com.rti.dds.infrastructure.HistoryQosPolicy has its kind set to HistoryQosPolicyKind.KEEP_ALL_HISTORY_QOS and com.rti.dds.infrastructure.ReliabilityQosPolicy.max_blocking_time is > 0.

[default] 1

[range] [1, 10000], <= max_concurrent_blocking_threads

int max_concurrent_blocking_threads

The maximum number of threads that are allowed to concurrently block on write call on the same com.rti.dds.publication.DataWriter.

This value only applies if com.rti.dds.infrastructure.HistoryQosPolicy has its kind set to HistoryQosPolicyKind.KEEP_ALL_HISTORY_QOS and com.rti.dds.infrastructure.ReliabilityQosPolicy.max_blocking_time is > 0.

[default] ResourceLimitsQosPolicy.LENGTH_UNLIMITED

[range] [1, 10000] or ResourceLimitsQosPolicy.LENGTH_UNLIMITED, >= initial_concurrent_blocking_threads

int max_remote_reader_filters

The maximum number of remote readers for which the writer will perform content-based filtering.

[default] 32

[range] [0, 32]

int max_batches

Represents the maximum number of batches a com.rti.dds.publication.DataWriter will manage.

[default] ResourceLimitsQosPolicy.LENGTH_UNLIMITED

When batching is enabled, the maximum number of samples that a com.rti.dds.publication.DataWriter can store is limited by this value and com.rti.dds.infrastructure.ResourceLimitsQosPolicy.max_samples.

[range] [1,100 million] or ResourceLimitsQosPolicy.LENGTH_UNLIMITED >= DDS_RtpsReliableWriterProtocol_t.heartbeats_per_max_samples if batching is enabled

See also:

com.rti.dds.infrastructure.BatchQosPolicy

int initial_batches

Represents the initial number of batches a com.rti.dds.publication.DataWriter will manage.

[default] 8

[range] [1,100 million]

See also:

com.rti.dds.infrastructure.BatchQosPolicy

int cookie_max_length

Represents the maximum length in bytes of a com.rti.dds.infrastructure.Cookie_t.

[default] ResourceLimitsQosPolicy.LENGTH_UNLIMITED

Sets the maximum allowed byte-sequence length of a com.rti.dds.infrastructure.Cookie_t used when writing with parameters

[range] [1,100 million] or ResourceLimitsQosPolicy.LENGTH_UNLIMITED

See also:

com.rti.dds.topic.example.FooDataWriter.write_w_params, com.rti.dds.topic.example.FooDataWriter.dispose_w_params, com.rti.dds.topic.example.FooDataWriter.register_instance_w_params, com.rti.dds.topic.example.FooDataWriter.unregister_instance_w_params

boolean replace_empty_instances

Whether or not to replace empty instances during instance replacement.

When a com.rti.dds.publication.DataWriter has more active instances than allowed by com.rti.dds.infrastructure.ResourceLimitsQosPolicy.max_instances, it tries to make room by replacing an existing instance. This field configures whether empty instances (i.e. instances with no samples) may be replaced. If set true, then a com.rti.dds.publication.DataWriter will first try reclaiming empty instances, before trying to replace whatever is specified by com.rti.dds.infrastructure.DataWriterResourceLimitsQosPolicy.instance_replacement.

[default] false

See also:

com.rti.dds.infrastructure.DataWriterResourceLimitsInstanceReplacementKind

boolean autoregister_instances

Whether or not to automatically register new instances.

[default] true

When set to true, it is possible to write with a non-NIL handle of an instance that is not registered: the write operation will succeed and the instance will be registered. Otherwise, that write operation would fail.

See also:

com.rti.dds.topic.example.FooDataWriter.write

int initial_virtual_writers

The initial number of virtual writers supported by a com.rti.dds.publication.DataWriter.

[default] 1

[range] [1, 1000000], or ResourceLimitsQosPolicy.LENGTH_UNLIMITED

int max_virtual_writers

The maximum number of virtual writers supported by a com.rti.dds.publication.DataWriter.

Sets the maximum number of unique virtual writers supported by a com.rti.dds.publication.DataWriter, where virtual writers are added when samples are written with the virtual writer GUID.

This field is specially relevant in the configuration of Persistence Service DataWriters since these DataWriters will publish samples on behalf of multiple virtual writers.

[default] ResourceLimitsQosPolicy.LENGTH_UNLIMITED

[range] [1, 1000000], or ResourceLimitsQosPolicy.LENGTH_UNLIMITED