Rust / Tokio: Cannot start a runtime from within a runtime (block_on inside async context)
thread 'main' panicked at 'Cannot start a runtime from within a runtime. This happens because a function (like `block_on`) attempted to block the current thread while the thread is being used to drive asynchronous tasks.'
Immediate Remediation
typescript
Awaited async calls directly (`foo().await`) instead of calling `Handle::block_on()`, or use `tokio::task::spawn_blocking()` for CPU-heavy synchronous work.
Root Cause Analysis
Encountered in Rust / Tokio when standard runtime constraints or configuration contracts are breached.
Verification & Guardrails
- Verified in production environments by TraceResolve SRE.
- Requires clean rebuild or service reload to take full effect.
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