Async::Service::Supervisor

Getting Started

This guide explains how to get started with async-service-supervisor to supervise and monitor worker processes in your Ruby applications.

Migration Guide

This guide explains how to migrate from async-container-supervisor to async-service-supervisor. The new version provides a cleaner API built on Async::Bus for improved reliability and maintainability.

Memory Monitor

This guide explains how to use the to detect and restart workers that exceed memory limits or develop memory leaks.

Process Monitor

This guide explains how to use the to log CPU and memory metrics for your worker processes.

Utilization Monitor

This guide explains how to use the to collect and aggregate application-level utilization metrics from your worker processes.

v0.14.0

• Add Worker#make_controller as an override point for providing a custom worker controller with additional RPCs.

v0.13.1

• Unlink shared memory file before opening on supervisor restart, preventing SIGBUS when workers still have the file mapped.

v0.13.0

• Add worker_count to UtilizationMonitor aggregated metrics per service, indicating how many workers contributed to each service's metrics (useful for utilization denominator).

v0.12.0

• Introduce UtilizationMonitor, that uses shared memory to track worker utilization metrics, like total and active requests, connections, etc.

v0.11.0

• Add state attribute to SupervisorController to store per-worker metadata (e.g., service name).
• Add state parameter to Worker#initialize to allow workers to provide state during registration.
• State is now accessible via supervisor_controller.state instead of connection.state (as it was in Async::Container::Supervisor).

v0.10.0

• Serialize register/remove and check! operations in MemoryMonitor to prevent race conditions.
• Remove memory_sample functionality - it wasn't very useful and added a lot of complexity.
• Add support for Memory::Leak::Cluster free_size_minimum: option.
• Remove extraneous "Memory leak detected!" logs.

v0.9.1

• Close Call queue if asynchronous call fails during dispatch - further messages will fail with ClosedQueueError.

v0.9.0

• Better handling of write failures in Connection::Call.dispatch, ensuring we don't leak calls.
• Robust monitor loop handling - restart on failure, and align loop iterations.
• Disable memory sampler by default and use text output format.
  • Introduce support for redirecting dump output to logs.

v0.8.0

• Add Async::Service::Supervisor::ProcessMonitor for logging CPU and memory metrics periodically.
• Fix documentation to use correct maximum_size_limit: parameter name for MemoryMonitor (was incorrectly documented as limit:).

v0.7.0

• If a memory leak is detected, sample memory usage for 60 seconds before exiting.