The Probe Lifecycle
1
Setting a Probe in VS Code
Right-click any line in an open source file and choose a probe type — Snapshot, Log, Counter, Metric, or Tic & Toc. The extension registers the probe definition with the broker.
2
Agent Probe Retrieval
The SDK agent polls the broker for active probes and dynamically instruments the target line in-memory. This happens live, with no process restarts.
3
Asynchronous Execution Hook
When execution hits the instrumented line, the agent captures variables, logs, counters, or metrics. The agent never pauses application threads.
4
Telemetry Enqueue & Flush
Captured telemetry is queued in-memory and flushed to the broker in asynchronous batches, ensuring zero impact on application request paths.
5
Real-Time Render in VS Code
The extension fetches the captured data and renders it beautifully inside your editor’s HyperProbe panel, presenting complete variable trees and call stacks.
Runtime Instrumentation Mechanics
HyperProbe does not modify your source files or your deployed build artifacts. Instead, it hooks into the runtime’s native introspection capabilities:- Node.js (V8): The Node SDK connects to the V8 debugger runtime using the native
inspectorprotocol. It places virtual break-hooks on specific compiled script locations. When hit, the callback grabs the local scope and call stack, returning control in microseconds. - Java (JVM): The Java Agent attaches via the standard
-javaagentflag. It performs lightweight, runtime bytecode manipulation using byte code libraries to inject capture instructions on-the-fly.
Architectural Topology
Built-In Safety Guardrails
The SDK agent runs a continuous safety monitor alongside your host application to prevent resource contention or performance impact:- Overhead Suspension: The agent tracks event loop lag and CPU usage. If thresholds are crossed, all probes are immediately suspended and the agent enters a cooldown status before automatically resuming.
- Global Throughput Throttling: Limits the maximum number of captures per second. Hits beyond this ceiling only increment the execution counter and bypass data serialization to save resources.
- Strict Payload Boundaries: Snapshots are restricted by maximum object depth, array length, and string size to ensure minimal memory usage.
- Local and Global Hit Limits: Each probe has a configurable hit limit. Once reached, its instrumentation is automatically and instantly uninstalled.
