@RunLLM is

preciseTopicPublishRateLimiterEnable

a configuration option on the broker?

Yes,

preciseTopicPublishRateLimiterEnable

(sometimes also referred to as

preciseTopicPublishRateLimitingEnable

) is a configuration option on the broker. When set to true, it enables a more accurate topic publish rate limiter for each broker, improving the effectiveness of publish rate limiting compared to the default implementation. This is confirmed in the context of Apache Pulsar broker configuration and related pull requests, such as this one. Would you like more detail on how to use or configure this option? Sources: - https://github.com/apache/pulsar/pull/20292 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.

@RunLLM is

preciseDispatcherFlowControl

a configuration option on the broker?

Yes,

preciseDispatcherFlowControl

is a broker configuration option. When enabled, it applies precise control on dispatch throttling by considering the number of messages per entry, improving accuracy in message dispatch rate limiting. By default, it is disabled. You can only enable either

preciseDispatcherFlowControl

or

dispatchThrottlingOnBatchMessageEnabled

at one time, as they are mutually exclusive. Would you like more detail on its effects or usage? Sources: - Throttling configurations - ServiceConfiguration.java 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.

@RunLLM Is

preciseTopicPublishRateLimiterEnable

still a necessary option in Pulsar

4.x

?

The necessity of

preciseTopicPublishRateLimiterEnable

in Pulsar 4.x is not explicitly documented in the provided sources. However, recent discussions and pull requests indicate that rate limiting was refactored in Pulsar 3.2.0 with PIP-322, and related PRs have been closed or marked stale, suggesting the option may no longer be required or is being replaced by improved mechanisms in 4.x (see here). Would you like more detail on the new rate limiting approach in Pulsar 4.x? Sources: - https://github.com/apache/pulsar/pull/20292 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.

@RunLLM For which load balancer is the option

lowerBoundarySheddingEnabled

used for?

The

lowerBoundarySheddingEnabled

option is used with the ThresholdShedder load balancer strategy. It allows the load balancer to trigger unloading from the highest-loaded broker when another broker's usage falls below the average minus the threshold, helping utilize idle or low-load brokers more effectively. Would you like more detail on how this option works or how to configure it? Sources: - ThresholdShedder documentation - ServiceConfiguration.java 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.

@RunLLM Can you explain the broker configuration option

minUnloadMessageThroughput

?

The

minUnloadMessageThroughput

broker configuration option sets the minimum throughput (in bytes/second) that must be met to trigger bundle unloading in the UniformLoadShedder and AvgShedder load balancing strategies. If the throughput to be offloaded is below this threshold, bundle unloading is skipped to avoid unnecessary or frequent unloads of low-traffic bundles. The default value is 1 MB/s (1 * 1024 * 1024 bytes). Would you like more detail on how this impacts load balancing? Sources: - ServiceConfiguration.java - Add threshold for each unload round for uniform load shedder 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.

@RunLLM Can you explain the broker configuration option

minUnloadMessage

?

The

minUnloadMessage

broker configuration option sets the minimum number of messages that must be met to trigger bundle unloading in the UniformLoadShedder and AvgShedder strategies. If the number of messages to be offloaded is below this threshold, the unload is skipped to prevent frequent unloading of low-traffic bundles. The default value is 1000 messages (source). Would you like more detail on how this affects load balancing? Sources: - ServiceConfiguration.java - Add threshold for each unload round for uniform load shedder 👍 0 button 👎 0 button 💡 Hint: Mention @runllm in the thread for followups.

Btw. Regarding the first question in the thread: https://github.com/apache/pulsar/pull/24249

Thank you! 👍 I was not sure but could tell there has been some rework around it