Profiling

profiling

Registry Trigger

Use when

• profile CPU memory IO database network rendering cloud cost unit economics and bottlenecks

Do not use when

• no task-local profiling decision is required

Skill Role

Define the symptom, hypothesis, profiler selection, representative comparison, measured bottleneck, re-profile, resource transfer, overhead, and artifact lifecycle. Exclude performance budgets and implementation.

High-Value Rules

• Select evidence from the symptom and falsifiable hypothesis. The measurement distinguishes compute, wait, allocation or retention, I/O, query, network, rendering, or unit-cost causes; familiarity alone is insufficient evidence.
• Use a representative, comparable workload. Match the request/data distribution, load shape, runtime/topology, dependency and cache/startup state, and relevant configuration before comparing baseline and candidate.
• Optimize only a measured bottleneck. Tie the dominant cost or wait to an owned source/configuration path, change the responsible constraint, and re-profile under matched conditions; report when the dominant constraint moves.
• Account for resource and cost transfer. A local latency/CPU gain can shift memory, I/O, queueing, egress, provider usage, rejected work, or unit cost elsewhere. Measure the affected system boundary and degraded outcomes.
• Bound profiling overhead. Record sampling/instrumentation effect, load and duration boundary, blast radius, stop condition, and cleanup; profiling that perturbs the system can invalidate its own evidence.
• Preserve behavior, security, and durability. Compare outputs, errors, state, required work, and protection boundaries alongside performance; a faster path that drops or changes required behavior is a defect.
• Own sensitive artifact lifecycle. Classify captured fields, minimize and redact collection, control access and storage, set retention/deletion or ephemeral cleanup, and prevent accidental persistence of traces, snapshots, queries, identifiers, or billing data.

Anti-Patterns

• Select a familiar profiler or optimization before the symptom and hypothesis identify what evidence could falsify the suspected cause.
• Compare unmatched workloads or environments, report one improved metric without re-profiling, or ignore a new dominant bottleneck and shifted resource or cost.
• Capture sensitive or high-overhead production artifacts without authority, blast-radius and stop limits, redaction, accountable storage, and deletion or cleanup.

Stop Conditions

Escalate unrepresentative comparison, unknown overhead, unauthorized or unstoppable production capture, unresolved artifact sensitivity/lifecycle, non-dominant bottlenecks, weakened protections, or changes to public contracts, schemas, external boundaries, capacity controls, or restart policy.

Output Contract

• profiling evidence with symptom and hypothesis, representative comparable workload, measured bottleneck and re-profile, resource/cost transfer, overhead boundary, correctness guard, and owned sensitive-artifact lifecycle

Targeted References