Resource Monitoring

This page describes the resource usage monitoring feature in the OpenScope Experimental Launcher.

Overview

Resource monitoring allows you to track CPU and memory usage for both the launcher and the acquisition subprocess during an experiment. The data is logged to a file for later analysis and troubleshooting.

How It Works

The launcher always logs resource usage statistics (CPU %, memory in MB) for both itself and (once started) the acquisition subprocess. The log is written continuously to launcher_metadata/resource_usage.json inside the session output folder. Logging occurs at a configurable interval (resource_log_interval parameter; default 5 seconds if not provided).

Configuration

Optional parameter to adjust interval:

{
  "resource_log_interval": 5
}

If omitted, the default interval of 5 seconds is used. There is no on/off toggle.

Log File Location

The resource usage log is saved as:

<session_output_folder>/launcher_metadata/resource_usage.json

Log File Format

The log file is a JSON array. Each entry contains:

timestamp: ISO format timestamp
launcher: CPU and memory usage for the launcher process
acquisition: CPU and memory usage for the acquisition subprocess (if running)

Example entry:

{
  "timestamp": "2025-06-28T12:34:56.789",
  "launcher": {"cpu_percent": 2.5, "memory_mb": 120.3},
  "acquisition": {"cpu_percent": 15.2, "memory_mb": 300.1}
}

Notes

Monitoring continues for the launcher even after the acquisition subprocess exits.
Data points are appended; previous samples are preserved for the entire session duration.

Troubleshooting

100% CPU usage means one full core; may be normal during computation.
If the log file is missing, verify the session folder was created and the launcher was not terminated immediately after start.