Скачать или смотреть Is It Safe to Add Future Callbacks for Each Publish in Kafka?

Explore whether adding `future callbacks` for each message published in Kafka can lead to memory issues and discover best practices for managing callbacks efficiently.
---
This video is based on the question https://stackoverflow.com/q/67823540/ asked by the user 'memoricab' ( https://stackoverflow.com/u/6431997/ ) and on the answer https://stackoverflow.com/a/67824192/ provided by the user 'Gary Russell' ( https://stackoverflow.com/u/1240763/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Is it fine to add future callback for each publish?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding Future Callbacks in Kafka Publishing

In the realm of messaging systems, such as Apache Kafka, developers often face the question of how best to manage asynchronous operations. One common concern is whether it is acceptable to add a future callback for each message published, especially regarding memory management.

The Issue at Hand

You've abstracted your message schema into an Event, which has various implementations. Each of these events is published as a message with its own method for handling callbacks. You've provided an example function that demonstrates this process:

[[See Video to Reveal this Text or Code Snippet]]

The primary concern here is whether adding a callback for every single event message could lead to memory issues due to previous callbacks lingering in memory and not being properly cleaned up.

The Answer: Yes, It's Fine!

The good news is that adding a callback for each event message is generally safe. Here's why:

1. Garbage Collection in Java

When you add a callback using the addCallback() method, you are essentially creating a temporary reference to that callback object. In Java, when there are no more references to an object, it becomes eligible for garbage collection.

Garbage Collection: This process runs on its own, periodically checking for objects that are no longer in use and reclaiming their memory. Thus, any callbacks that are no longer referenced will be cleaned up by the garbage collector.

2. Avoiding Memory Issues

Even though each callback is created for every message sent, they do not accumulate indefinitely. Once the message is processed and there are no further references to the future or the callback, they will be removed from memory.

Best Practices

While the above discussion reassures the safety of your current implementation, you can still consider adopting some best practices to ensure optimal performance:

Monitor Memory Usage: Keep an eye on your application's memory usage to spot any potential leaks early.

Manage Callbacks Efficiently: If you notice that your callbacks are creating a significant load, consider implementing a more centralized management of callbacks rather than associating a separate callback with each message.

Exception Handling: Ensure that your callback methods handle exceptions gracefully to avoid unexpected behavior.

Conclusion

In summary, it's perfectly fine to add future callbacks for each published message in Kafka, as they will be cleaned up by the garbage collector once there are no more references. By following the best practices mentioned, you can maintain the health of your application while taking advantage of asynchronous message handling.

By implementing these strategies, you’ll find that Kafka can handle your event-driven architecture smoothly and efficiently.