Configuration Guide
Transport LBT-RU Reliability Options

LBT-RU's reliability options closely model LBT-RM's. The descriptions and illustrations in Transport LBT-RM Reliability Options generally apply to LBT-RU, with appropriate option name changes.


Reference  <-


transport_lbtru_ignore_interval (source)  <-

The interval to ignore NAKs after a retransmission is sent.
This option affects the transport session underlying the source rather than the source itself. The transport session uses the value from the first source created on the session and ignores subsequent sources.
Refer to Source Object for additional information.
Scope: source
Type: lbm_ulong_t
Units: milliseconds
Default value: 500 (0.5 seconds)
When to Set: Can only be set during object initialization.


transport_lbtru_nak_backoff_interval (receiver)  <-

The maximum interval between transmissions of a single NAK.
For LBT-RU transport sessions only. The actual value is randomized (to reduce self-similar behaviors) and is uniform on the range [0.5*interval, 1.5*interval]. This option affects the transport session underlying the receiver rather than the receiver itself. The transport session uses the value from the first receiver created on the session and ignores subsequent receivers. Refer to Receiver Object and Interrelated Configuration Options for additional information.
Scope: receiver
Type: lbm_ulong_t
Units: milliseconds
Default value: 200 (0.2 seconds)
When to Set: Can only be set during object initialization.


transport_lbtru_nak_generation_interval (receiver)  <-

The maximum time that a piece of data may be outstanding before the data is unrecoverably lost.
For LBT-RU transport sessions only. Although the minimum valid value is 5 milliseconds, larger values are advisable. This option affects the transport session underlying the receiver rather than the receiver itself. The transport session uses the value from the first receiver created on the session and ignores subsequent receivers. Refer to Receiver Object and Interrelated Configuration Options for additional information.
Scope: receiver
Type: lbm_ulong_t
Units: milliseconds
Default value: 10000 (10 seconds)
When to Set: Can only be set during object initialization.


transport_lbtru_nak_initial_backoff_interval (receiver)  <-

The interval between loss detection and transmission of the first NAK.
For LBT-RU transport sessions only.
The actual time the receiver will wait to NAK is random. The algorithm used to determine the time range is (1/2 * initial_backoff_interval - 3/2 * initial_backoff_interval). This can result in a wait interval longer than the specified value. A value of 0 indicates that the receiver should immediately send a NAK.
Scope: receiver
Type: lbm_ulong_t
Units: milliseconds
Default value: 0 (disabled)
When to Set: Can only be set during object initialization.


transport_lbtru_nak_suppress_interval (receiver)  <-

The maximum interval to suppress sending NAKs after an NCF is received.
For LBT-RU transport sessions only. This option affects the transport session underlying the receiver rather than the receiver itself. The transport session uses the value from the first receiver created on the session and ignores subsequent receivers. Refer to Receiver Object for additional information.
Scope: receiver
Type: lbm_ulong_t
Units: milliseconds
Default value: 1000 (1 second)
When to Set: Can only be set during object initialization.


transport_lbtru_receiver_socket_buffer (context)  <-

Value used to set SO_RCVBUF value of the LBT-RU receiver unicast socket (both sender and receiver sides).
In some cases the OS will not allow all of this value to be used. See Socket Buffer Sizes for platform-dependent information.
See also our white paper Topics in High Performance Messaging for background and guidelines on UDP buffer sizing.
Scope: context
Type: lbm_ulong_t
Units: bytes
Default value: 8388608 (8MB)
When to Set: Can only be set during object initialization.


transport_lbtru_source_socket_buffer (context)  <-

Value used to set SO_SNDBUF value of the LBT-RU send multicast socket.
In some cases the OS will not allow all of this value to be used. See Socket Buffer Sizes for platform-dependent information. A value of 0 instructs UM to use the OS default.
Scope: context
Type: lbm_ulong_t
Units: bytes
Default value: 1048576 (1MB)
When to Set: Can only be set during object initialization.


transport_lbtru_transmission_window_limit (source)  <-

Caps the total amount of memory that a transmission window uses, which includes data and overhead.
For example, if the transport_lbtru_transmission_window_size (source) is 24 MB (default) and the source sends 20 byte messages with the "flush" flag, the actual amount of memory used can approximate 300 MB. The default value of this option does not limit the transmission window.
Scope: source
Type: size_t
Units: bytes
Default value: 0 (zero)
When to Set: Can only be set during object initialization.


transport_lbtru_transmission_window_size (source)  <-

The maximum amount of buffered data that the LBT-RU source is allowed to retain for retransmissions.
The minimum valid value is 65536 bytes. This option affects the transport session underlying the source rather than the source itself. The transport session uses the value from the first source created on the session and ignores subsequent sources. Refer to Source Object for additional information.
Scope: source
Type: size_t
Units: bytes
Default value: 25165824 (24 MB)
When to Set: Can only be set during object initialization.