# src
## Purpose
Provides a benchmarking harness for measuring Blueprint job execution time, CPU cores, and RAM usage. Designed around a pluggable async runtime abstraction with a built-in Tokio implementation.
## Contents (one hop)
### Subdirectories
- (none)
### Files
- `lib.rs` - Defines the `Runtime` trait, `TokioRuntime` implementation, `Bencher` harness, and `BenchmarkSummary` result type with human-readable `Display` formatting.
## Key APIs (no snippets)
- `Runtime` trait -- abstraction for executing futures to completion (`block_on`).
- `TokioRuntime` -- `Runtime` impl that delegates to `tokio::runtime::Handle::current()`.
- `Bencher::new(threads, runtime)` -- creates a harness with a specified core count and runtime.
- `Bencher::block_on(future)` -- runs an async workload on the configured runtime.
- `Bencher::stop(name, job_id)` -- ends the benchmark, captures elapsed time and process memory via `sysinfo`, returns a `BenchmarkSummary`.
- `BenchmarkSummary` -- contains name, job ID, elapsed duration, core count, and RAM usage; implements `Display` with auto-scaled units (B/KB/MB/GB).
## Relationships
- Depends on `blueprint-std` for `Future`, `Instant`, `Duration`, and `fmt` abstractions.
- Depends on `sysinfo` (behind the `std` feature) for process memory measurement.
- Depends on `tokio` for the default runtime implementation.
- Used by blueprint authors to benchmark job execution as part of profiling workflows.