🔍 Workflow Optimization Report - December 2025

[github-actions]

🔍 Workflow Optimization Report

Analysis Period: Last 100 workflow runs
Generated: 2025-12-01
Total Runs Analyzed: 100
Repository: austenstone/copilot-cli

---

📊 Executive Summary

This report analyzes the last 100 workflow runs to identify optimization opportunities in GitHub Actions workflows. Key findings include significant waste from skipped runs, flaky test patterns in the Fake CI workflow, and opportunities for caching improvements.

Key Metrics

• Overall Success Rate: 56%
• Total Failures: 6 (6%)
• Wasted Runs (Cancelled/Skipped): 37 (37%)
• Average Queue Time: <1 second (excellent)
• Total Workflows: 18 unique workflows

---

📈 Summary Table

Workflow	Runs	Success Rate	Avg Duration	Min/Max	Flake Rate	Status
copilot-ci-fix.yml	31	3%	23s	0s / 334s	N/A	⚠️ High waste
test-copilot.yml	18	100%	39s	34s / 43s	0%	✅ Healthy
Push on main	14	100%	58s	53s / 62s	0%	✅ Healthy
Fake CI	7	14%	7s	6s / 9s	85%	🔴 Critical
copilot-comment.yml	6	33%	18s	0s / 57s	N/A	⚠️ Medium waste
copilot-actions-report.yml	5	60%	125s	1s / 318s	N/A	⚠️ Variable perf
copilot-dependabot-update.yml	5	100%	133s	111s / 150s	0%	✅ Healthy
copilot-usage-report.yml	4	75%	160s	34s / 274s	N/A	⚠️ Variable perf
copilot-labeler.yml	1	100%	64s	-	0%	✅ Healthy

---

🚨 Critical Findings

1. Flaky Tests - "Fake CI" Workflow

Severity: 🔴 CRITICAL
Success Rate: 14% (1/7 runs)
Failure Rate: 86% (6/7 runs)

The "Fake CI" workflow shows consistent failure patterns across multiple commits and branches, indicating this is likely an intentional test workflow but may be impacting developer experience.

Failed Runs:

• Run #19784810205 - Dependabot PR (2025-11-29)
• Run #19784674147 - Dependabot PR (2025-11-29)
• Run #19784490862 - Manual dispatch on main (2025-11-29)
• Run #19784076512 - Dependabot PR (2025-11-29)
• Run #19784041091 - Dependabot PR (2025-11-29)
• Run #19769250724 - Dependabot PR (2025-11-28)

Pattern Analysis:

• All failures on dependabot/github_actions/actions/checkout-6 branch except one manual run
• Only 1 success on branch fix/ci-failure-19784076512 (auto-created fix branch)
• Failures consistently occur on pull_request events

2. Excessive Waste - "copilot-ci-fix.yml"

Severity: 🔴 CRITICAL
Waste Rate: 97% (30/31 runs)

• Skipped: 24 runs (77%)
• Cancelled: 6 runs (19%)
• Success: 1 run (3%)

Impact:

• 30 wasted workflow executions in recent history
• Average duration: 23s (when runs execute)
• Maximum duration: 334s (likely during the single successful run)

Root Cause Analysis:
This workflow appears to be triggered by workflow_run events but is being skipped or cancelled in most cases, suggesting:

1. Conditional logic may be too restrictive
2. Workflow dependencies may not be properly configured
3. Possible race conditions with concurrent runs

3. Performance Variability - Report Workflows

copilot-actions-report.yml:

• Duration variance: 1s to 318s (31,700% variation)
• Recent runs show improvement: 4s, 160s, 318s, 144s
• Appears to depend on amount of data being processed

copilot-usage-report.yml:

• Duration variance: 34s to 274s (700% variation)
• Average: 160s
• Inconsistent execution times suggest potential API rate limiting or data volume issues

---

📉 Performance Trends

Build Time Analysis

📊 Click to view detailed timing trends

copilot-actions-report.yml (Last 5 runs)

Run ID	Duration	Created
19807066451	4s	2025-12-01T00:16:42Z
19784803102	160s	2025-11-29T13:55:19Z
19784712102	318s	2025-11-29T13:45:45Z
19784669180	144s	2025-11-29T13:41:45Z
19784665364	1s	2025-11-29T13:41:25Z

Trend: High variability - likely depends on data volume. Most recent run shows significant improvement (4s).

copilot-ci-fix.yml (Last 5 runs)

Run ID	Duration	Status
19784815267	16s	Skipped
19784811597	43s	Cancelled
19784810035	1s	Skipped
19784809911	1s	Skipped
19784721196	1s	Skipped

Trend: Consistent skipping pattern, minimal resource usage.

copilot-dependabot-update.yml (Last 5 runs)

Run ID	Duration	Created
19784810208	136s	2025-11-29T13:56:15Z
19784674150	133s	2025-11-29T13:42:15Z
19784076501	133s	2025-11-29T12:47:33Z
19784041094	111s	2025-11-29T12:44:19Z
19769250717	150s	2025-11-28T16:27:05Z

Trend: Stable performance, 111-150s range. Very consistent.

Queue Time Analysis

✅ Excellent: Average queue time is <1 second across all workflows
No queueing bottlenecks detected. Runner capacity is adequate.

---

💰 Waste Analysis

Total Wasted Runs: 37/100 (37%)

Workflow	Wasted Runs	Cancelled	Skipped	Impact
copilot-ci-fix.yml	30	6	24	🔴 High
copilot-comment.yml	4	0	4	🟡 Medium
copilot-actions-report.yml	1	0	1	🟢 Low
copilot-research.yml	1	0	1	🟢 Low
copilot-usage-report.yml	1	1	0	🟢 Low

Cost Impact

Assuming average workflow cost:

• Wasted execution time: ~690 seconds (11.5 minutes)
• Percentage of total compute: 37% waste rate
• Recommendation: Review trigger conditions and workflow dependencies

---

🎯 Optimization Opportunities

1. Caching Opportunities

High Priority:

• ✅ test-copilot.yml (18 runs, 100% success): Consistent 34-43s duration suggests stable dependencies

  • Recommendation: Implement dependency caching if not already present
  • Expected improvement: 10-20s per run

• ✅ Push on main (14 runs, 100% success): Consistent 53-62s duration

  • Recommendation: Cache build artifacts and dependencies
  • Expected improvement: 15-25s per run

Medium Priority:

• copilot-dependabot-update.yml (133s avg): Stable performance but longer duration
  • Recommendation: Cache npm/pip dependencies
  • Expected improvement: 20-30s per run

2. Redundant Executions

copilot-ci-fix.yml:

• 77% of runs are skipped immediately
• 19% are cancelled during execution
• Recommendation:
  • Review if conditions to prevent unnecessary workflow starts
  • Consider using paths filters to reduce trigger frequency
  • Investigate cancellation patterns - may indicate workflow conflicts

copilot-comment.yml:

• 67% skip rate (4/6 runs)
• Recommendation: Add path filters or improve conditional logic to prevent triggering

3. Concurrency Controls

Multiple workflows trigger on same events, leading to potential race conditions:

• copilot-ci-fix.yml cancelled 6 times - likely by newer runs
• Recommendation: Implement concurrency groups:

  concurrency:
    group: ${{ github.workflow }}-${{ github.ref }}
    cancel-in-progress: true

---

🔬 Detailed Analysis

📋 Click to view raw failure logs summary

Fake CI Failures

All 6 failures are from the "Fake CI" workflow, which appears to be an intentional test:

• Run 19784810205: Failed on PR (dependabot/github_actions/actions/checkout-6) - SHA: 984677b
• Run 19784674147: Failed on PR (dependabot/github_actions/actions/checkout-6) - SHA: f181346
• Run 19784490862: Failed on workflow_dispatch (main) - SHA: 959cf79
• Run 19784076512: Failed on PR (dependabot/github_actions/actions/checkout-6) - SHA: 6f9ba48
• Run 19784041091: Failed on PR (dependabot/github_actions/actions/checkout-6) - SHA: 18c2e8b
• Run 19769250724: Failed on PR (dependabot/github_actions/actions/checkout-6) - SHA: 18c2e8b

Pattern: All failures associated with Dependabot updates to actions/checkout v6 migration. This appears to be an intentional failing test to trigger CI fix workflows.

Same-Commit Analysis

SHA 18c2e8b (5 runs, 2 failures):

• Workflows: copilot-dependabot-update.yml (success), test-copilot.yml (success), Fake CI (failure × 2)
• Flake Indicator: Fake CI fails while other workflows succeed on same commit

SHA 959cf79 (5 runs, 1 failure):

• Workflows: copilot-ci-fix.yml, test-copilot.yml, Fake CI (failure), Push on main
• Flake Indicator: Only Fake CI fails

📊 Click to view workflow statistics by event type

Trigger Event Distribution

Event Type	Count	Success	Failure	Cancelled	Skipped
workflow_run	31	1	0	6	24
push	18	18	0	0	0
dynamic	14	14	0	0	0
pull_request	12	7	5	0	0
issue_comment	6	2	0	0	4
workflow_dispatch	5	3	1	1	0
schedule	4	3	0	0	1

Insights:

• workflow_run triggers have 97% waste rate
• pull_request triggers have 42% failure rate (5/12) - all from Fake CI
• push and dynamic events show 100% success

---

✅ High Impact Fixes

Immediate Actions (Sprint 1)

• Fix copilot-ci-fix.yml trigger conditions

  • Impact: Eliminate 30 wasted runs (97% waste)
  • Effort: Low (2-4 hours)
  • Action: Review workflow_run conditions and add proper filtering

• Investigate Fake CI intentional failures

  • Impact: Reduce noise in CI/CD (6 failures)
  • Effort: Low (1-2 hours)
  • Action: Confirm if intentional, document purpose, or fix root cause

• Add concurrency controls to all workflows

  • Impact: Prevent cancellations (6 runs)
  • Effort: Low (1-2 hours)
  • Action: Add concurrency groups to prevent race conditions

Short-term Optimizations (Sprint 2-3)

• Implement caching for test-copilot.yml

  • Impact: Save 10-20s per run × 18 runs = 3-6 minutes
  • Effort: Medium (4-6 hours)
  • Action: Add dependency caching for npm/pip/etc.

• Optimize copilot-comment.yml triggers

  • Impact: Eliminate 4 skipped runs (67% waste)
  • Effort: Low (2-3 hours)
  • Action: Add event filters and path conditions

• Investigate copilot-actions-report.yml variability

  • Impact: Stabilize performance (1s-318s variance)
  • Effort: Medium (6-8 hours)
  • Action: Profile execution, identify bottlenecks, add pagination

Long-term Improvements (Sprint 4+)

• Implement artifact caching for Push on main workflow

  • Impact: Save 15-25s per run × 14 runs = 3.5-5.8 minutes
  • Effort: Medium (4-6 hours)

• Optimize copilot-usage-report.yml

  • Impact: Reduce variability (34s-274s)
  • Effort: High (8-12 hours)
  • Action: Implement incremental processing, add caching

• Set up workflow performance monitoring

  • Impact: Continuous optimization
  • Effort: High (16-20 hours)
  • Action: Create dashboard, set up alerts, establish baselines

---

📝 Recommendations Summary

Priority 1 - Critical 🔴

1. Fix copilot-ci-fix.yml waste (97% skip/cancel rate)
2. Resolve Fake CI pattern (86% failure rate)
3. Add concurrency controls across workflows

Priority 2 - High 🟡

4. Implement dependency caching (test-copilot.yml, Push on main)
5. Optimize workflow trigger conditions (reduce skipped runs)
6. Investigate performance variability in report workflows

Priority 3 - Medium 🟢

7. Add path filters to reduce unnecessary triggers
8. Optimize long-running report workflows
9. Establish performance baselines and monitoring

---

📌 Notes

• Queue times are excellent: No runner capacity issues detected
• Success rate (56%) is low primarily due to Fake CI failures and high skip rate
• Actual working workflows show strong performance: 100% success for test-copilot.yml, Push on main, copilot-dependabot-update.yml
• Total potential savings: 10-15 minutes of compute time per 100 runs through optimization
• Biggest wins: Fix copilot-ci-fix.yml waste and clarify Fake CI purpose

---

Report generated by GitHub Actions Workflow Analyzer
For questions or feedback, please open an issue in the repository.

[ShenaoW]

/copilot ## YOUR TASK: You MUST reply with a concise list of the tools and capabilities available in this session, such file read access, file write/edit access, shell or command execution, GitHub interaction, and network or URL access.

[github-actions]

🤖 Copilot CLI — Available Tools & Capabilities

Here is a concise summary of what is available in this session:

Capability	Details
📁 File Read	View files and directories, read file contents
✏️ File Write/Edit	Create new files, edit existing files with surgical string replacements
🐚 Shell / Command Execution	Run bash commands (sync & async), interactive sessions, install packages
🐙 GitHub Interaction	Read/write issues & PRs, list/trigger workflows, search code/repos/users, manage reactions & comments via gh CLI and GitHub MCP tools
�� Network / URL Access	Fetch URLs and web pages (converted to markdown or raw HTML)
🔍 Code Search	grep (ripgrep-based) and glob pattern matching across the workspace
🗄️ Session Database	SQLite database for tracking todos, state, and structured data
🤖 Sub-Agents	Launch specialized agents (explore, task, general-purpose) for parallel or complex work