Always-on tracing for production and preview traffic
Vercel has introduced always-on tracing for production and preview traffic, enabling real-time debugging without reproducing requests. The feature samples live traffic based on user-defined rules, with pricing at $0.50 per 1 million span units.
Vercel’s new always-on tracing feature continuously collects traces from live production and preview traffic, unlike session tracing which only captures requests from a user’s own browser. The system samples traffic according to configurable rules, allowing developers to set trace rates for specific environments or path prefixes. No data is collected until a rule is added, ensuring users only pay for traces they explicitly enable. Infrastructure and outbound fetch spans are automatically included in traces.
To enhance tracing granularity, developers can instrument their applications using the @vercel/otel package to add framework and custom spans. Traces can be viewed either through the Logs interface or by running the vercel traces get command in the CLI. The feature is currently in beta and available to teams on all Vercel plans, including Hobby, Pro, and Enterprise tiers.
Pricing for tracing is set at $0.50 per 1 million span units, with costs incurred only for collected traces. Trace retention varies by plan: 1 hour for Hobby, 1 day for Pro, and 3 days for Enterprise. This aligns costs with usage while ensuring sufficient data for debugging purposes.
To begin using always-on tracing, users can configure rules via Settings → Tracing or directly from the settings icon in the Logs interface. Detailed documentation is available to guide setup and customization. The feature aims to simplify debugging by providing real-time visibility into live traffic without manual reproduction of requests.