py2rs-review-r3-io-concurrency

name	py2rs-review-r3-io-concurrency
description	[DRAFT] 第 3 轮 IO、并发与运行时人体工学审查。对一个迁移单元或已收批的 review batch 检查阻塞 IO、async 边界、取消、重试、并发限制和运行时嵌套；默认审查不改生产代码。

R3 IO And Concurrency Review

R3 关注系统是否会因为 IO、运行时边界或无界并发而卡住、死锁或难以恢复。

Preconditions

• The R0 behavior report exists.
• R2 error/tracing review is complete or explicitly deferred.
• Every in-scope unit's runtime context is known: CLI, service, Tauri, Python bridge, batch worker or library.

Review Focus

• Blocking IO in async command/service paths.
• Nested runtime creation such as Tokio inside an existing Tokio runtime.
• Cancellation behavior for long-running work.
• Retry and backoff for recoverable network/external failures.
• Progress/event/log behavior for long operations.
• Concurrency limits: semaphore, queue, bounded worker pool or documented serial behavior.
• Trace/context propagation across spawned tasks.

Workflow

1. Confirm the unit or closed review batch, included unit ids and runtime environments.
2. Inspect IO paths: filesystem, network, DB, process, bridge and event channels.
3. Run narrow non-mutating checks or tests when practical.
4. Look for user-visible hangs, unbounded waits and stuck partial state.
5. Save a report with promotion decision.

Code Changes

Default review-gate mode does not edit production code. If explicitly asked to remediate:

• Keep public behavior stable.
• Preserve cancellation/progress contracts.
• Avoid broad algorithm or storage redesigns.
• Require the R0 behavior gate to be rerun after changes.
• Do not write the final pass report for your own patch.

Report

Use project convention or:

reviews/YYYY-MM-DD-<unit-or-batch-id>-async-ergonomics.md

Include:

• Scope reviewed
• Included unit ids and per-unit verdicts (not_required only when the manifest does not require R3 for that unit)
• Runtime/IO interfaces inspected
• Findings ordered by severity
• Checks or benchmarks run
• Residual risk
• Promotion decision

Non-Negotiables

• No blocking HTTP/file transfer inside async command paths unless isolated and justified.
• No unbounded concurrency.
• No swallowed cancellation.
• Do not change algorithms for speed here unless the change is strictly required by the IO model and R0 still passes.