x-review-performance

Global Output Policy

• Language: English ONLY.
• Tone: Technical, Direct, and Concise.
• Efficiency: Remove all conversational fillers and greetings to save tokens.

Skill: Performance Specialist Review

Purpose

Review code changes for performance best practices: N+1 query detection, connection pool sizing, async patterns, pagination on collections, caching strategy, timeout configuration, circuit breaker usage, thread safety, resource cleanup, lazy loading, batch operations, and index usage.

When to Use

• Pre-PR quality validation for performance concerns
• Reviewing database query patterns
• Checking resilience patterns (timeouts, circuit breakers)
• Validating resource management

Triggers

• /x-review-performance 42 -- review PR #42 for performance
• /x-review-performance src/main/java/com/example/repository/ -- review specific paths
• /x-review-performance -- review all current changes

Parameters

Parameter	Type	Required	Default	Description
target	String	No	(current changes)	PR number or file paths to review

Knowledge Pack References

Pack	Files	Purpose
resilience	knowledge/resilience/index.md	Circuit breaker, rate limiting, timeout, retry, bulkhead patterns

Checklist (13 Items, Max Score: /26)

Each item scores 0 (missing), 1 (partial), or 2 (fully compliant).

Query Performance (PERF-01 to PERF-02)

#	Item	Score
PERF-01	No N+1 queries (eager fetching or batch loading where needed)	/2
PERF-02	Connection pool sized appropriately for expected load	/2

Async & Concurrency (PERF-03, PERF-09)

#	Item	Score
PERF-03	Async processing where applicable (non-blocking I/O)	/2
PERF-09	Thread safety verified (no shared mutable state without synchronization)	/2

Collection & Data (PERF-04 to PERF-06)

#	Item	Score
PERF-04	Pagination on collection endpoints (no unbounded result sets)	/2
PERF-05	Caching strategy defined for frequently accessed data	/2
PERF-06	No unbounded lists in memory (streams or pagination for large datasets)	/2

Resilience (PERF-07 to PERF-08)

#	Item	Score
PERF-07	Timeout configured on all external calls (HTTP, DB, message broker)	/2
PERF-08	Circuit breaker on external service calls	/2

Resource Management (PERF-10 to PERF-13)

#	Item	Score
PERF-10	Resource cleanup in finally/try-with-resources (connections, streams, files)	/2
PERF-11	Lazy loading for expensive initializations	/2
PERF-12	Batch operations for bulk data processing (not row-by-row)	/2
PERF-13	Database indexes used for queried columns	/2

Workflow

Step 1 -- Gather Context

Read the resilience knowledge pack:

• knowledge/resilience/index.md

Step 2 -- Identify Changed Files

Determine scope: PR diff or specified paths. Focus on repository, service, and adapter layers.

Step 3 -- Query Analysis

Scan for N+1 patterns, missing indexes, unbounded queries.

Step 4 -- Resilience Check

Verify timeout, circuit breaker, and retry configurations on external calls.

Step 5 -- Resource Management Check

Verify proper resource cleanup, connection pool configuration, and batch operations.

Step 6 -- Concurrency Check

Check for thread safety issues, shared mutable state, and proper synchronization.

Step 7 -- Generate Report

Produce the scored report.

Output Format

ENGINEER: Performance
STORY: [story-id or change description]
SCORE: XX/26

STATUS: PASS | FAIL | PARTIAL

### PASSED
- [PERF-XX] [Item description]

### FAILED
- [PERF-XX] [Item description]
  - Finding: [file:line] [issue description]
  - Fix: [remediation guidance]

### PARTIAL
- [PERF-XX] [Item description]
  - Finding: [partial compliance details]

Error Handling

Scenario	Action
No repository/service code found	Report INFO: no performance-relevant code discovered
No external calls detected	Skip PERF-07, PERF-08 and note N/A
No database queries detected	Skip PERF-01, PERF-02, PERF-13 and note N/A