Rate Limiter

Class: RateLimiterBlockV1

Source: inference.core.workflows.core_steps.flow_control.rate_limiter.v1.RateLimiterBlockV1

The Rate Limiter block controls the execution frequency of a branch within a Workflow by enforcing a cooldown period. It ensures that the connected steps do not run more frequently than a specified interval, helping to manage resource usage and prevent over-execution.

Block usage

Rate Limiter is useful when you have two blocks that are directly connected, as shown below:

--- input_a --> ┌───────────┐ ┌───────────┐ --- input_b --> │ step_1 │ --> output_a --> │ step_2 │ --- input_c --> └───────────┘ └───────────┘

If you want to throttle the Step 2 execution rate - you should apply rate limiter in between:

• keep the existing blocks configuration as is (do not change connections)

• set depends_on reference of Rate Limiter into output_a

• set next_steps reference to be a list referring to [$steps.step_2]

• adjust cooldown_seconds to specify what is the number of seconds that must be awaited before next time when step_2 is fired

Cooldown limitations

Current implementation of cooldown is limited to video processing - using this block in context of a Workflow that is run behind HTTP service (Roboflow Hosted API, Dedicated Deployment or self-hosted inference server) will have no effect for processing HTTP requests.

Type identifier

Use the following identifier in step "type" field: roboflow_core/rate_limiter@v1to add the block as as step in your workflow.

Properties

Name	Type	Description	Refs
name	str	Enter a unique identifier for this step..	❌
cooldown_seconds	float	The minimum number of seconds between allowed executions..	❌

The Refs column marks possibility to parametrise the property with dynamic values available in workflow runtime. See Bindings for more info.

Available Connections

Compatible Blocks

Check what blocks you can connect to Rate Limiter in version v1.

• inputs: Bounding Box Visualization, Twilio SMS Notification, Llama 3.2 Vision, Stability AI Outpainting, Overlap Filter, Model Comparison Visualization, Image Slicer, Background Color Visualization, Mask Visualization, QR Code Generator, Classification Label Visualization, Buffer, Polygon Visualization, Florence-2 Model, Instance Segmentation Model, Environment Secrets Store, Local File Sink, Grid Visualization, Clip Comparison, Instance Segmentation Model, LMM For Classification, Dot Visualization, Pixel Color Count, Keypoint Detection Model, Halo Visualization, VLM as Detector, Icon Visualization, Crop Visualization, Slack Notification, Pixelate Visualization, CLIP Embedding Model, SIFT, Single-Label Classification Model, Stitch OCR Detections, Data Aggregator, QR Code Detection, JSON Parser, Cosine Similarity, SmolVLM2, Camera Focus, Florence-2 Model, Line Counter Visualization, Dynamic Crop, Byte Tracker, Roboflow Dataset Upload, Segment Anything 2 Model, Cache Set, Webhook Sink, YOLO-World Model, Identify Outliers, Byte Tracker, Image Slicer, OpenAI, Image Preprocessing, Stability AI Inpainting, Keypoint Visualization, Barcode Detection, Identify Changes, Multi-Label Classification Model, Stability AI Image Generation, Detections Filter, Model Monitoring Inference Aggregator, Keypoint Detection Model, Detections Merge, First Non Empty Or Default, Moondream2, Image Threshold, Detections Stabilizer, SIFT Comparison, LMM, Gaze Detection, Corner Visualization, Distance Measurement, Dimension Collapse, Image Contours, Time in Zone, CogVLM, Rate Limiter, Detections Transformation, Property Definition, Trace Visualization, Perspective Correction, Path Deviation, Continue If, SIFT Comparison, Byte Tracker, Image Convert Grayscale, PTZ Tracking (ONVIF).md), Line Counter, Google Gemini, Relative Static Crop, Ellipse Visualization, Object Detection Model, Dynamic Zone, Polygon Zone Visualization, Time in Zone, Triangle Visualization, Size Measurement, Single-Label Classification Model, CSV Formatter, Path Deviation, Stitch Images, Color Visualization, Email Notification, Blur Visualization, VLM as Classifier, Expression, Anthropic Claude, Absolute Static Crop, Label Visualization, Detection Offset, Detections Consensus, Cache Get, Multi-Label Classification Model, Reference Path Visualization, Velocity, Camera Calibration, Image Blur, Qwen2.5-VL, OpenAI, VLM as Classifier, Circle Visualization, Template Matching, Dominant Color, Delta Filter, OCR Model, Depth Estimation, Bounding Rectangle, OpenAI, Line Counter, Detections Classes Replacement, Roboflow Dataset Upload, Clip Comparison, Object Detection Model, VLM as Detector, Detections Stitch, Perception Encoder Embedding Model, Roboflow Custom Metadata, Google Vision OCR
• outputs: None

Input and Output Bindings

The available connections depend on its binding kinds. Check what binding kinds Rate Limiter in version v1 has.

Bindings

• input

  • depends_on (*): Step immediately preceding this block..
  • next_steps (step): Steps to execute if allowed by the rate limit..
  • video_reference_image (image): Reference to a video frame to use for timestamp generation (if running faster than realtime on recorded video)..

• output

Example JSON definition of step Rate Limiter in version v1

{
    "name": "<your_step_name_here>",
    "type": "roboflow_core/rate_limiter@v1",
    "cooldown_seconds": 1.0,
    "depends_on": "$steps.model",
    "next_steps": [
        "$steps.upload"
    ],
    "video_reference_image": "$inputs.image"
}