Distinguish elapsed time from resource limits
See this course’s project requirements
A local supervisor for two harmless supplied Python scripts, with process IDs, captured output, return-code classification, timeout cleanup and a resource-limit decision record.
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What to include
- Produce an owned-child lifecycle record with actual PID and explicit control scope.
- Retain an explicit bounded command/context specification and pre-launch mode rejection.
- Create an actual stdout/stderr/return-code classification matrix for successful and failed modes.
- Demonstrate bounded timeout cleanup and retain accurate interrupted-task classification.
- Document elapsed-time evidence and a clear unimplemented-resource-controls boundary.
- Deliver the owned supervisor with dynamic observations, tested lifecycle branches, and explicit resource/platform limits.
Review and revise
Use these criteria to check your work and choose what to improve.
- The implementation or declared simulation follows the supplied contract and retains inspectable original inputs.
- Normal, boundary and rejected cases are recorded with expected versus observed results.
- The changed case has a correct explanation and does not rely on hidden state.
- The project includes source, outputs, instructions and honest tool, privacy and verification limits.
Want more background?
The idea in everyday life
owned_worker.py has harmless ok, fail, and slow modes. local_supervisor.py starts only that owned Python file, captures its small output, classifies return status, and cleans it up after a bounded timeout. test-processes.py runs five checks with no outside commands or accounts.
monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known.
Distinguish elapsed time from resource limits — original worked practice
monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known.
owned_worker.py has harmless ok, fail, and slow modes. local_supervisor.py starts only that owned Python file, captures its small output, classifies return status, and cleans it up after a bounded timeout. test-processes.py runs five checks with no outside commands or accounts.
1. Step 1
Read start=time.monotonic and the final elapsed_seconds calculation.
You should see: The run records elapsed duration.
monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known.
2. Step 2
Compare completion timeout with the recorded total including cleanup.
You should see: Total elapsed can include cleanup beyond the first deadline.
monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known.
3. Step 3
Inspect the known child’s small fixed output and harmless sleep.
You should see: communicate collects bounded-by-source output in this exercise.
monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known.
4. Step 4
Write a resource decision: allow only these supplied workers; larger/untrusted workers require additional quotas/output handling not implemented here.
You should see: A time-versus-resource-limit decision record.
monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known.
What to finish
Document elapsed-time evidence and a clear unimplemented-resource-controls boundary.
Watch for this
Treating a completion timeout as a general memory/CPU/output sandbox.
How can I tell I understand it?
Demonstrate the rule: monotonic elapsed time measures a duration; timeout bounds waiting. Neither enforces memory, output-volume, or CPU quotas, so the supplied child must stay small and known. Use the supplied variant to distinguish a changed result from a broken implementation.
Quick knowledge check
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Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
Source & access notes · checked 2026-10-01
Relevant documented module/API behavior inspected during expansion authoring; actual execution evidence is recorded separately. No grant eligibility is established.
Access: Official page retrieved with the web reader on 2026-10-01. Documentation reading does not certify execution in every native tool or browser.
Reuse: Original local practice files, fictional data, worked examples and questions. Concepts paraphrased and linked; source exercises are not copied.
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