Improved understanding of profiles

Oct 13, 2025 by pinkandtrash.com 125 views

Introduction

In the current implementation of the WorkloadExecutor, the number of blocking task threads spawned is fixed at 512. This can make it challenging to understand a profile, as the default tokio runtime configuration is used. To address this issue, we propose making the number of blocking task threads configurable via the CLI. This will allow users to customize the behavior of the WorkloadExecutor to suit their specific needs.

Current Implementation

The WorkloadExecutor currently uses either the current tokio runtime or creates a new one. However, if the default tokio runtime configuration is used, 512 blocking task threads are spawned. This can lead to difficulties in understanding a profile, as the default configuration is not suitable for all use cases.

The handle for creating the WorkloadExecutor is located in the following code snippet:

https://github.com/paradigmxyz/reth/blob/d7397bbc3a8a1c73429e925b7f38f674eab5c351/crates/engine/tree/src/tree/payload_processor/executor.rs#L64-L79

Proposed Solution

To make the number of blocking task threads configurable, we propose adding an Option to the WorkloadExecutor to allow users to specify the number of threads. If the value is None (which should be the default), the current code will be used. Otherwise, the RuntimeBuilder and worker_threads will be used to create the runtime.

The RuntimeBuilder provides a flexible way to configure the tokio runtime, allowing users to customize the number of worker threads. By using this approach, users will be able to specify the number of blocking task threads that are spawned, making it easier to understand a profile.

Implementation Details

To implement this change, we will need to modify the WorkloadExecutor to accept an Option for the number of blocking task threads. If the value is None, the current code will be used. Otherwise, the RuntimeBuilder will be used to create the runtime with the specified number of worker threads.

Here is an example of how the modified WorkloadExecutor might look:

struct WorkloadExecutor {
    // ...
    blocking_threads: Option<usize>,
}

impl WorkloadExecutor {
    fn new(blocking_threads: Option<usize>) -> Self {
        // ...
    }

    fn run(&self) {
        // ...
    }
}

In this example, the WorkloadExecutor has an Option field blocking_threads that allows users to specify the number of blocking task threads. If the value is None, the current code will be used. Otherwise, the RuntimeBuilder will be used to create the runtime with the specified number of worker threads.

Benefits

Making the number of blocking task threads configurable via the CLI will provide several benefits, including:

Improved understanding of profiles: By allowing users to customize the number of blocking task threads, it will be easier to understand a profile and identify performance bottlenecks.
Increased flexibility: Users will be able to tailor the behavior of the WorkloadExecutor to suit their specific needs, making it a more versatile tool.
Better performance: By allowing users to specify the number of blocking task threads, it will be possible to optimize the performance of the WorkloadExecutor for specific use cases.

Conclusion

In conclusion, making the number of blocking task threads configurable via the CLI will provide several benefits, including improved understanding of profiles, increased flexibility, and better performance. By modifying the WorkloadExecutor to accept an Option for the number of blocking task threads, users will be able to customize the behavior of the WorkloadExecutor to suit their specific needs.

Future Work

Future work will focus on implementing the proposed solution and testing it to ensure that it meets the requirements. Additionally, we will need to document the changes and provide guidance on how to use the new feature.

References

https://github.com/paradigmxyz/reth/blob/d7397bbc3a8a1c73429e925b7f38f674eab5c351/crates/engine/tree/src/tree/payload_processor/executor.rs#L64-L79
https://docs.rs/tokio/latest/tokio/runtime/struct.Builder.html#method.worker_threads
Make WorkloadExecutor Blocking Task Threads Configurable: Q&A ===========================================================

Introduction

In our previous article, we discussed the proposal to make the number of blocking task threads configurable via the CLI for the WorkloadExecutor. This change will provide several benefits, including improved understanding of profiles, increased flexibility, and better performance. In this article, we will answer some frequently asked questions (FAQs) about this proposal.

Q: Why is the current implementation of the `WorkloadExecutor` not suitable for all use cases?

A: The current implementation of the WorkloadExecutor uses the default tokio runtime configuration, which spawns 512 blocking task threads. This can make it challenging to understand a profile, as the default configuration is not suitable for all use cases.

Q: How will the proposed solution improve the understanding of profiles?

A: By making the number of blocking task threads configurable via the CLI, users will be able to customize the behavior of the WorkloadExecutor to suit their specific needs. This will make it easier to understand a profile and identify performance bottlenecks.

Q: What are the benefits of making the number of blocking task threads configurable?

A: The benefits of making the number of blocking task threads configurable include:

Improved understanding of profiles: By allowing users to customize the number of blocking task threads, it will be easier to understand a profile and identify performance bottlenecks.
Increased flexibility: Users will be able to tailor the behavior of the WorkloadExecutor to suit their specific needs, making it a more versatile tool.
Better performance: By allowing users to specify the number of blocking task threads, it will be possible to optimize the performance of the WorkloadExecutor for specific use cases.

Q: How will the proposed solution be implemented?

A: The proposed solution will be implemented by modifying the WorkloadExecutor to accept an Option for the number of blocking task threads. If the value is None (which should be the default), the current code will be used. Otherwise, the RuntimeBuilder and worker_threads will be used to create the runtime with the specified number of worker threads.

Q: What are the next steps for implementing the proposed solution?

A: The next steps for implementing the proposed solution include:

Modifying the WorkloadExecutor to accept an Option for the number of blocking task threads
Implementing the RuntimeBuilder and worker_threads to create the runtime with the specified number of worker threads
Testing the proposed solution to ensure that it meets the requirements

Q: How will the proposed solution be tested?

A: The proposed solution will be tested to ensure that it meets the requirements. This will involve:

Unit testing: The proposed solution will be tested using unit tests to ensure that it works correctly.
Integration testing: The proposed solution will be tested using integration tests to ensure that it works correctly with other components.
Performance testing: The proposed solution will be tested using performance tests to ensure that it performs correctly.

Q: What are the potential risks associated with the proposed solution?

A: The potential risks associated with the proposed solution include:

Increased complexity: The proposed solution may increase the complexity of the WorkloadExecutor, which could make it more difficult to maintain and debug.
Performance issues: The proposed solution may introduce performance issues if not implemented correctly.
Compatibility issues: The proposed solution may introduce compatibility issues if not implemented correctly.

Conclusion

In conclusion, making the number of blocking task threads configurable via the CLI for the WorkloadExecutor will provide several benefits, including improved understanding of profiles, increased flexibility, and better performance. By answering the FAQs about this proposal, we hope to provide a better understanding of the proposed solution and its benefits.