Middleware Memory Management

Use these QoS fields to configure the memory usage of the middleware, including various initial and max limits.

Use these QoS fields to configure the memory usage of the middleware, including various initial and max limits.

Basic Settings

dds::core::policy::ResourceLimits	max_samples
	<<basic>> <<spec>> Represents the maximum samples the middleware can store for any one dds::pub::DataWriter (or dds::sub::DataReader).
dds::core::policy::ResourceLimits	max_instances
	<<basic>> <<spec>> Represents the maximum number of instances a dds::pub::DataWriter (or dds::sub::DataReader) can manage.
dds::core::policy::ResourceLimits	initial_samples
	<<basic>> <<extension>> Represents the initial samples the middleware will store for any one dds::pub::DataWriter (or dds::sub::DataReader).
dds::core::policy::ResourceLimits	initial_instances
	<<basic>> <<extension>> Represents the initial number of instances a dds::pub::DataWriter (or dds::sub::DataReader) will manage.
rti::core::MonitoringLoggingDistributionSettings	max_historical_logs
	<<basic>> <<extension>> The number of log messages that RTI Monitoring Library 2.0 will keep as history.

Advanced Settings

rti::core::PersistentStorageSettings	writer_memory_state
	<<extension>> Determines how much state will be kept in memory by the durable writer history in order to avoid accessing the persistent storage in disk.
dds::core::policy::DurabilityService	max_samples
	<<spec>> Part of resource limits QoS policy to apply when feeding a late joiner.
dds::core::policy::DurabilityService	max_instances
	<<spec>> Part of resource limits QoS policy to apply when feeding a late joiner.
dds::core::policy::DurabilityService	max_samples_per_instance
	<<spec>> Part of resource limits QoS policy to apply when feeding a late joiner.
dds::core::policy::ResourceLimits	max_samples_per_instance
	<<spec>> Represents the maximum number of samples of any one instance a dds::pub::DataWriter (or dds::sub::DataReader) can manage.
rti::core::policy::DataReaderResourceLimits	max_remote_writers
	<<extension>> The maximum number of remote writers from which a dds::sub::DataReader may read, including all instances.
rti::core::policy::DataReaderResourceLimits	max_remote_writers_per_instance
	<<extension>> The maximum number of remote writers from which a dds::sub::DataReader may read a single instance.
rti::core::policy::DataReaderResourceLimits	max_samples_per_remote_writer
	<<extension>> The maximum number of out-of-order samples from a given remote dds::pub::DataWriter that a dds::sub::DataReader may store when maintaining a reliable connection to the dds::pub::DataWriter.
rti::core::policy::DataReaderResourceLimits	max_infos
	<<extension>> The maximum number of info units that a dds::sub::DataReader can use to store dds::sub::SampleInfo.
rti::core::policy::DataReaderResourceLimits	initial_remote_writers
	<<extension>> The initial number of remote writers from which a dds::sub::DataReader may read, including all instances.
rti::core::policy::DataReaderResourceLimits	initial_remote_writers_per_instance
	<<extension>> The initial number of remote writers from which a dds::sub::DataReader may read a single instance.
rti::core::policy::DataReaderResourceLimits	initial_infos
	<<extension>> The initial number of info units that a dds::sub::DataReader can have, which are used to store dds::sub::SampleInfo.
rti::core::policy::DataReaderResourceLimits	initial_outstanding_reads
	<<extension>> The initial number of outstanding calls to read/take (or one of their variants) on the same dds::sub::DataReader for which memory has not been returned by calling dds::sub::LoanedSamples::return_loan().
rti::core::policy::DataReaderResourceLimits	max_outstanding_reads
	<<extension>> The maximum number of outstanding read/take calls (or one of their variants) on the same dds::sub::DataReader for which memory has not been returned by calling dds::sub::LoanedSamples::return_loan().
rti::core::policy::DataReaderResourceLimits	max_samples_per_read
	<<extension>> The maximum number of data samples that the application can receive from the middleware in a single call to dds::sub::DataReader::read or dds::sub::DataReader::take. If more data exists in the middleware, the application will need to issue multiple read/take calls.
rti::core::policy::DataReaderResourceLimits	max_fragmented_samples
	<<extension>> The maximum number of samples for which the dds::sub::DataReader may store fragments at a given point in time.
rti::core::policy::DataReaderResourceLimits	initial_fragmented_samples
	<<extension>> The initial number of samples for which a dds::sub::DataReader may store fragments.
rti::core::policy::DataReaderResourceLimits	max_fragmented_samples_per_remote_writer
	<<extension>> The maximum number of samples per remote writer for which a dds::sub::DataReader may store fragments.
rti::core::policy::DataReaderResourceLimits	max_fragments_per_sample
	<<extension>> Maximum number of fragments for a single sample.
rti::core::policy::DataReaderResourceLimits	dynamically_allocate_fragmented_samples
	<<extension>> Determines whether the dds::sub::DataReader pre-allocates storage for storing fragmented samples.
rti::core::policy::DataReaderResourceLimits	max_total_instances
	<<extension>> Maximum number of instances for which a DataReader will keep state.
rti::core::policy::DataReaderResourceLimits	max_remote_virtual_writers
	<<extension>> The maximum number of remote virtual writers from which a dds::sub::DataReader may read, including all instances.
rti::core::policy::DataReaderResourceLimits	initial_remote_virtual_writers
	<<extension>> The initial number of remote virtual writers from which a dds::sub::DataReader may read, including all instances.
rti::core::policy::DataReaderResourceLimits	max_remote_virtual_writers_per_instance
	<<extension>> The maximum number of virtual remote writers that can be associated with an instance.
rti::core::policy::DataReaderResourceLimits	initial_remote_virtual_writers_per_instance
	<<extension>> The initial number of virtual remote writers per instance.
rti::core::policy::DataReaderResourceLimits	max_remote_writers_per_sample
	<<extension>> The maximum number of remote writers allowed to write the same sample.
rti::core::policy::DataReaderResourceLimits	max_query_condition_filters
	<<extension>> The maximum number of query condition filters a reader is allowed.
rti::core::policy::DataReaderResourceLimits	max_app_ack_response_length
	<<extension>> Maximum length of application-level acknowledgment response data
rti::core::policy::DataReaderResourceLimits	keep_minimum_state_for_instances
	<<extension>> Whether or not keep a minimum instance state for up to rti::core::policy::DataReaderResourceLimits::max_total_instances.
rti::core::policy::DataReaderResourceLimits	initial_topic_queries
	<<extension>> The initial number of TopicQueries allocated by a dds::sub::DataReader.
rti::core::policy::DataReaderResourceLimits	max_topic_queries
	<<extension>> The maximum number of active TopicQueries that a dds::sub::DataReader can create.
rti::core::policy::DataReaderResourceLimits	shmem_ref_transfer_mode_attached_segment_allocation
	<<extension>> Allocation resource for the shared memory segments attached by the dds::sub::DataReader.
rti::core::policy::DataReaderResourceLimits	instance_replacement
	<<extension>> Sets the kind of instances allowed to be replaced for each instance state (dds::sub::status::InstanceState) when a DataReader reaches dds::core::policy::ResourceLimits::max_instances.
rti::core::policy::DataReaderResourceLimits	autopurge_remote_not_alive_writer_delay
	<<extension>> Maximum duration for which the dds::sub::DataReader will maintain information regarding a dds::pub::DataWriter once the dds::pub::DataWriter has become not alive.
rti::core::policy::DataWriterResourceLimits	initial_concurrent_blocking_threads
	[DEPRECATED] <<extension>> The initial number of threads that are allowed to concurrently block on write call on the same dds::pub::DataWriter.
rti::core::policy::DataWriterResourceLimits	max_concurrent_blocking_threads
	[DEPRECATED] <<extension>> The maximum number of threads that are allowed to concurrently block on write call on the same dds::pub::DataWriter.
rti::core::policy::DataWriterResourceLimits	max_remote_reader_filters
	<<extension>> The maximum number of remote DataReaders for which the dds::pub::DataWriter will perform content-based filtering.
rti::core::policy::DataWriterResourceLimits	initial_batches
	<<extension>> Represents the initial number of batches a dds::pub::DataWriter will manage.
rti::core::policy::DataWriterResourceLimits	max_batches
	<<extension>> Represents the maximum number of batches a dds::pub::DataWriter will manage.
rti::core::policy::DataWriterResourceLimits	instance_replacement
	<<extension>> Sets the kinds of instances allowed to be replaced when instance resource limits are reached.
rti::core::policy::DataWriterResourceLimits	replace_empty_instances
	<<extension>> Whether or not to replace empty instances during instance replacement
rti::core::policy::DataWriterResourceLimits	max_virtual_writers
	<<extension>> The maximum number of virtual writers supported by a dds::pub::DataWriter
rti::core::policy::DataWriterResourceLimits	initial_virtual_writers
	<<extension>> The initial number of virtual writers supported by a dds::pub::DataWriter
rti::core::policy::DataWriterResourceLimits	max_remote_readers
	<<extension>> The maximum number of remote readers supported by a dds::pub::DataWriter
rti::core::policy::DataWriterResourceLimits	max_app_ack_remote_readers
	<<extension>> The maximum number of application-level acknowledging remote readers supported by a dds::pub::DataWriter
rti::core::policy::DataWriterResourceLimits	initial_active_topic_queries
	<<extension>> Represents the initial number of active topic queries a dds::pub::DataWriter will manage.
rti::core::policy::DataWriterResourceLimits	max_active_topic_queries
	<<extension>> Represents the maximum number of active topic queries a dds::pub::DataWriter will manage.
rti::core::policy::DataWriterResourceLimits	writer_loaned_sample_allocation
	<<extension>> Represents the allocation settings of loaned samples managed by a dds::pub::DataWriter.
rti::core::policy::SystemResourceLimits	max_objects_per_thread
	[DEPRECATED] <<extension>> The maximum number of objects that can be stored per thread for a DomainParticipantFactory.
rti::core::policy::SystemResourceLimits	initial_objects_per_thread
	<<extension>> The number of objects per thread for a DomainParticipantFactory for which infrastructure will initially be allocated.
rti::core::policy::DomainParticipantResourceLimits	local_writer_allocation
	<<extension>> Allocation settings applied to local DataWriters.
rti::core::policy::DomainParticipantResourceLimits	local_reader_allocation
	<<extension>> Allocation settings applied to local DataReaders.
rti::core::policy::DomainParticipantResourceLimits	local_publisher_allocation
	<<extension>> Allocation settings applied to local Publisher.
rti::core::policy::DomainParticipantResourceLimits	local_subscriber_allocation
	<<extension>> Allocation settings applied to local Subscriber.
rti::core::policy::DomainParticipantResourceLimits	local_topic_allocation
	<<extension>> Allocation settings applied to local Topic.
rti::core::policy::DomainParticipantResourceLimits	remote_writer_allocation
	<<extension>> Allocation settings applied to remote DataWriters.
rti::core::policy::DomainParticipantResourceLimits	remote_reader_allocation
	<<extension>> Allocation settings applied to remote DataReaders.
rti::core::policy::DomainParticipantResourceLimits	remote_participant_allocation
	<<extension>> Allocation settings applied to remote DomainParticipants.
rti::core::policy::DomainParticipantResourceLimits	matching_writer_reader_pair_allocation
	<<extension>> Allocation settings applied to matching local writer and remote/local reader pairs.
rti::core::policy::DomainParticipantResourceLimits	matching_reader_writer_pair_allocation
	<<extension>> Allocation settings applied to matching local reader and remote/local writer pairs.
rti::core::policy::DomainParticipantResourceLimits	ignored_entity_allocation
	<<extension>> Allocation settings applied to ignored entities.
rti::core::policy::DomainParticipantResourceLimits	content_filtered_topic_allocation
	<<extension>> Allocation settings applied to content filtered topic.
rti::core::policy::DomainParticipantResourceLimits	content_filter_allocation
	<<extension>> Allocation settings applied to content filter.
rti::core::policy::DomainParticipantResourceLimits	read_condition_allocation
	<<extension>> Allocation settings applied to read condition pool.
rti::core::policy::DomainParticipantResourceLimits	query_condition_allocation
	<<extension>> Allocation settings applied to query condition pool.
rti::core::policy::DomainParticipantResourceLimits	outstanding_asynchronous_sample_allocation
	<<extension>> Allocation settings applied to the maximum number of samples (from all dds::pub::DataWriter) waiting to be asynchronously written.
rti::core::policy::DomainParticipantResourceLimits	flow_controller_allocation
	<<extension>> Allocation settings applied to flow controllers.
rti::core::policy::DomainParticipantResourceLimits	local_writer_hash_buckets
	[DEPRECATED] <<extension>> Hash_Buckets settings applied to local DataWriters.
rti::core::policy::DomainParticipantResourceLimits	local_reader_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for local DataReaders.
rti::core::policy::DomainParticipantResourceLimits	local_publisher_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for local Publisher.
rti::core::policy::DomainParticipantResourceLimits	local_subscriber_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for local Subscriber.
rti::core::policy::DomainParticipantResourceLimits	local_topic_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for local Topic.
rti::core::policy::DomainParticipantResourceLimits	remote_writer_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for remote DataWriters.
rti::core::policy::DomainParticipantResourceLimits	remote_reader_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for remote DataReaders.
rti::core::policy::DomainParticipantResourceLimits	remote_participant_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for remote DomainParticipants.
rti::core::policy::DomainParticipantResourceLimits	matching_writer_reader_pair_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for matching local writer and remote/local reader pairs.
rti::core::policy::DomainParticipantResourceLimits	matching_reader_writer_pair_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for matching local reader and remote/local writer pairs.
rti::core::policy::DomainParticipantResourceLimits	ignored_entity_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for ignored entities.
rti::core::policy::DomainParticipantResourceLimits	content_filtered_topic_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for content filtered topics.
rti::core::policy::DomainParticipantResourceLimits	content_filter_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for content filters.
rti::core::policy::DomainParticipantResourceLimits	flow_controller_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for flow controllers.
rti::core::policy::DomainParticipantResourceLimits	max_gather_destinations
	<<extension>> Maximum number of destinations per RTI Connext send.
rti::core::policy::DomainParticipantResourceLimits	participant_user_data_max_length
	<<extension>> Maximum length of user data in dds::domain::qos::DomainParticipantQos and dds::topic::ParticipantBuiltinTopicData
rti::core::policy::DomainParticipantResourceLimits	topic_data_max_length
	<<extension>> Maximum length of topic data in dds::topic::qos::TopicQos, dds::topic::TopicBuiltinTopicData, dds::topic::PublicationBuiltinTopicData and dds::topic::SubscriptionBuiltinTopicData
rti::core::policy::DomainParticipantResourceLimits	publisher_group_data_max_length
	<<extension>> Maximum length of group data in dds::pub::qos::PublisherQos and dds::topic::PublicationBuiltinTopicData
rti::core::policy::DomainParticipantResourceLimits	subscriber_group_data_max_length
	<<extension>> Maximum length of group data in dds::sub::qos::SubscriberQos and dds::topic::SubscriptionBuiltinTopicData
rti::core::policy::DomainParticipantResourceLimits	writer_user_data_max_length
	<<extension>> Maximum length of user data in dds::pub::qos::DataWriterQos and dds::topic::PublicationBuiltinTopicData
rti::core::policy::DomainParticipantResourceLimits	reader_user_data_max_length
	<<extension>> Maximum length of user data in dds::sub::qos::DataReaderQos and dds::topic::SubscriptionBuiltinTopicData
rti::core::policy::DomainParticipantResourceLimits	max_partitions
	<<extension>> Maximum number of partition name strings allowable in a dds::core::policy::Partition.
rti::core::policy::DomainParticipantResourceLimits	max_partition_cumulative_characters
	<<extension>> Maximum number of combined characters allowable in all partition names in a dds::core::policy::Partition.
rti::core::policy::DomainParticipantResourceLimits	type_code_max_serialized_length
	[DEPRECATED] <<extension>> Maximum size of serialized string for type code.
rti::core::policy::DomainParticipantResourceLimits	type_object_max_serialized_length
	<<extension>> The maximum length, in bytes, that the buffer to serialize a TypeObject can consume.
rti::core::policy::DomainParticipantResourceLimits	type_object_max_deserialized_length
	<<extension>> The maximum number of bytes that a deserialized TypeObject can consume.
rti::core::policy::DomainParticipantResourceLimits	deserialized_type_object_dynamic_allocation_threshold
	<<extension>> A threshold, in bytes, for dynamic memory allocation for the deserialized TypeObject.
rti::core::policy::DomainParticipantResourceLimits	serialized_type_object_dynamic_allocation_threshold
	<<extension>> A threshold, in bytes, for dynamic memory allocation for the serialized TypeObject.
rti::core::policy::DomainParticipantResourceLimits	contentfilter_property_max_length
	<<extension>> This field is the maximum length of all data related to a Content-filtered topic.
rti::core::policy::DomainParticipantResourceLimits	channel_seq_max_length
	<<extension>> Maximum number of channels that can be specified in rti::core::policy::MultiChannel for MultiChannel DataWriters.
rti::core::policy::DomainParticipantResourceLimits	channel_filter_expression_max_length
	<<extension>> Maximum length of a channel rti::core::ChannelSettings::filter_expression in a MultiChannel DataWriter.
rti::core::policy::DomainParticipantResourceLimits	participant_property_list_max_length
	<<extension>> Maximum number of properties associated with the dds::domain::DomainParticipant.
rti::core::policy::DomainParticipantResourceLimits	participant_property_string_max_length
	<<extension>> Maximum string length of the properties associated with the dds::domain::DomainParticipant.
rti::core::policy::DomainParticipantResourceLimits	writer_property_list_max_length
	<<extension>> Maximum number of properties associated with a dds::pub::DataWriter.
rti::core::policy::DomainParticipantResourceLimits	writer_property_string_max_length
	<<extension>> Maximum string length of the properties associated with a dds::pub::DataWriter.
rti::core::policy::DomainParticipantResourceLimits	reader_property_list_max_length
	<<extension>> Maximum number of properties associated with a dds::sub::DataReader.
rti::core::policy::DomainParticipantResourceLimits	reader_property_string_max_length
	<<extension>> Maximum string length of the properties associated with a dds::sub::DataReader.
rti::core::policy::DomainParticipantResourceLimits	max_endpoint_groups
	<<extension>> Maximum number of rti::core::EndpointGroup allowable in a rti::core::policy::Availability.
rti::core::policy::DomainParticipantResourceLimits	max_endpoint_group_cumulative_characters
	<<extension>> Maximum number of combined role_name characters allowed in all rti::core::EndpointGroup in a rti::core::policy::Availability.
rti::core::policy::DomainParticipantResourceLimits	transport_info_list_max_length
	<<extension>> Maximum number of installed transports to send and receive information about in dds::topic::ParticipantBuiltinTopicData::transport_info.
rti::core::policy::DomainParticipantResourceLimits	ignored_entity_replacement_kind
	[DEPRECATED] <<extension>> Replacement policy for the ignored entities. It sets what entity can be replaced when resource limits set in rti::core::policy::DomainParticipantResourceLimits::ignored_entity_allocation are reached.
rti::core::policy::DomainParticipantResourceLimits	remote_topic_query_allocation
	<<extension>> Allocation settings applied to remote TopicQueries.
rti::core::policy::DomainParticipantResourceLimits	remote_topic_query_hash_buckets
	[DEPRECATED] <<extension>> Number of hash buckets for remote TopicQueries.
rti::core::policy::DomainParticipantResourceLimits	writer_data_tag_list_max_length
	<<extension>> Maximum number of data tags associated with a dds::pub::DataWriter.
rti::core::policy::DomainParticipantResourceLimits	writer_data_tag_string_max_length
	<<extension>> Maximum string length of the data tags associated with a dds::pub::DataWriter.
rti::core::policy::DomainParticipantResourceLimits	reader_data_tag_list_max_length
	<<extension>> Maximum number of data tags associated with a dds::sub::DataReader.
rti::core::policy::DomainParticipantResourceLimits	reader_data_tag_string_max_length
	<<extension>> Maximum string length of the data tags associated with a dds::sub::DataReader.
rti::core::policy::DomainParticipantResourceLimits	shmem_ref_transfer_mode_max_segments
	<<extension>> Maximum number of segments created by all DataWriters belonging to a dds::domain::DomainParticipant.
rti::core::policy::Event	initial_count
	<<extension>> The initial number of events.
rti::core::policy::Event	max_count
	<<extension>> The maximum number of events.
rti::core::policy::Database	initial_records
	<<extension>> The initial number of total records.
rti::core::policy::Database	max_skiplist_level
	[DEPRECATED] <<extension>> The maximum level of the skiplist.
rti::core::policy::Database	initial_weak_references
	<<extension>> The initial number of weak references.
rti::core::policy::Database	max_weak_references
	<<extension>> The maximum number of weak references.
rti::core::policy::ReceiverPool	buffer_size
	<<extension>> The receive buffer size in bytes.
rti::core::policy::ReceiverPool	buffer_alignment
	[DEPRECATED] <<extension>> The receive buffer alignment.
rti::core::policy::DiscoveryConfig	participant_reader_resource_limits
	<<extension>> Resource limits.
rti::core::policy::DiscoveryConfig	publication_reader_resource_limits
	<<extension>> Resource limits.
rti::core::policy::DiscoveryConfig	subscription_reader_resource_limits
	<<extension>> Resource limits.
rti::core::policy::DiscoveryConfig	participant_configuration_reader_resource_limits
	<<extension>> Resource limits for the built-in topic participant configuration reader.
rti::core::policy::BuiltinTopicReaderResourceLimits	initial_samples
	<<extension>> Initial number of samples.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_samples
	<<extension>> Maximum number of samples.
rti::core::policy::BuiltinTopicReaderResourceLimits	initial_infos
	<<extension>> Initial number of sample infos.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_infos
	<<extension>> Maximum number of sample infos.
rti::core::policy::BuiltinTopicReaderResourceLimits	initial_outstanding_reads
	<<extension>> The initial number of outstanding reads that have not called finish yet on the same built-in topic dds::sub::DataReader.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_outstanding_reads
	<<extension>> The maximum number of outstanding reads that have not called finish yet on the same built-in topic dds::sub::DataReader.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_samples_per_read
	<<extension>> Maximum number of samples that can be read/taken on a same built-in topic dds::sub::DataReader.
rti::core::policy::BuiltinTopicReaderResourceLimits	disable_fragmentation_support
	[DEPRECATED] <<extension>> Determines whether the built-in topic dds::sub::DataReader can receive fragmented samples.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_fragmented_samples
	<<extension>> The maximum number of samples for which the built-in topic dds::sub::DataReader may store fragments at a given point in time.
rti::core::policy::BuiltinTopicReaderResourceLimits	initial_fragmented_samples
	<<extension>> The initial number of samples for which a built-in topic dds::sub::DataReader may store fragments.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_fragmented_samples_per_remote_writer
	<<extension>> The maximum number of samples per remote writer for which a built-in topic dds::sub::DataReader may store fragments.
rti::core::policy::BuiltinTopicReaderResourceLimits	max_fragments_per_sample
	<<extension>> Maximum number of fragments for a single sample.
rti::core::policy::BuiltinTopicReaderResourceLimits	dynamically_allocate_fragmented_samples
	<<extension>> Determines whether the built-in topic dds::sub::DataReader pre-allocates storage for storing fragmented samples.
rti::core::ThreadSettings	stack_size
	The thread stack-size.
rti::config::Logger	max_bytes_per_file
	<<extension>> Specifies the maximum number of bytes a single file can contain
rti::config::Logger	max_files
	<<extension>> Specifies the maximum number of files to create before overwritting the previous ones.