afv-library/skills/debugging-apex-logs/references/log-analysis-tools.md

Log Analysis Tools

This guide covers tools for analyzing Salesforce debug logs, with a focus on performance profiling and bottleneck identification.

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Recommended: Apex Log Analyzer (VS Code)

The Apex Log Analyzer is a free VS Code extension that provides visual analysis of Apex debug logs.

Installation

1. Open VS Code
2. Go to Extensions (Ctrl+Shift+X / Cmd+Shift+X)
3. Search "Apex Log Analyzer"
4. Install "Apex Log Analyzer" by FinancialForce

Or install via command line:

code --install-extension FinancialForce.lana

Key Features

Feature	Description	Use Case
Flame Charts	Visual execution timeline	Find slow methods at a glance
Call Tree	Hierarchical method calls	Trace execution paths
Database Analysis	SOQL/DML highlighting	Find query hotspots
Timeline View	Execution over time	See parallel operations
Limit Summary	Governor limit usage	Quick health check

How to Use

1. Get a debug log:

   sf apex get log --log-id 07Lxx0000000000 --target-org my-sandbox -o debug.log
   

2. Open in VS Code:

   • Open the .log file
   • Click "Analyze Log" button in the editor toolbar
   • Or use Command Palette: "Apex Log: Analyze Log"

3. Navigate the visualization:

   • Flame Chart: Wider bars = more time spent
   • Click methods to see details
   • Hover for exact timing
   • Filter to focus on specific operations

Reading Flame Charts

┌─────────────────────────────────────────────────────────────┐
│ FLAME CHART INTERPRETATION                                   │
├─────────────────────────────────────────────────────────────┤
│                                                              │
│  ████████████████████████████████████  AccountTrigger       │
│    ██████████████████  AccountService.processAccounts       │
│      ██████████  ← BOTTLENECK: Wide bar = slow operation    │
│        ████  SOQL query                                      │
│      ████████████  Another slow method                       │
│                                                              │
│  Time flows left → right                                     │
│  Width = execution time                                      │
│  Stack depth = call hierarchy                                │
│                                                              │
└─────────────────────────────────────────────────────────────┘

Bottleneck Indicators:

• Wide bars at lower levels (deep in call stack)
• Multiple identical bars (repeated operations)
• SOQL/DML bars inside loop patterns

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SF CLI Debug Commands

List Available Logs

# List recent logs
sf apex list log --target-org my-sandbox --json

# Output includes:
# - Log ID
# - Start time
# - Operation type
# - User
# - Size

Download Logs

# Download specific log
sf apex get log --log-id 07Lxx0000000000 --target-org my-sandbox

# Save to file
sf apex get log --log-id 07Lxx0000000000 --target-org my-sandbox > debug.log

# Download with number
sf apex get log --number 1 --target-org my-sandbox  # Most recent

Real-Time Log Streaming

# Tail logs in real-time (like `tail -f`)
sf apex tail log --target-org my-sandbox

# With color highlighting
sf apex tail log --target-org my-sandbox --color

# Use an existing debug level when setting the trace flag
sf apex tail log --target-org my-sandbox --debug-level MyDebugLevel

# Skip trace flag setup when a trace flag is already configured
sf apex tail log --target-org my-sandbox --skip-trace-flag

Set Debug Level

# Create trace flag via SFDX
sf data create record \
  --sobject TraceFlag \
  --values "TracedEntityId='005xx...' LogType='USER_DEBUG' StartDate='2024-01-01T00:00:00' ExpirationDate='2024-01-02T00:00:00'" \
  --target-org my-sandbox

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Manual Log Analysis (grep/ripgrep)

When you need quick analysis without visual tools:

Find All SOQL Queries

# Count SOQL queries
rg "SOQL_EXECUTE_BEGIN" debug.log | wc -l

# See query text
rg "SOQL_EXECUTE_BEGIN" debug.log

# Find SOQL in loops (query appears multiple times on same line)
rg "SOQL_EXECUTE_BEGIN" debug.log | sort | uniq -c | sort -rn | head -10

Find Large Result Sets

# Find queries returning many rows
rg "SOQL_EXECUTE_END.*\[\d{4,} rows\]" debug.log

Check Governor Limits

# Find limit snapshots
rg "LIMIT_USAGE" debug.log | tail -20

# Find approaching limits (>80%)
rg "CPU_TIME" debug.log | tail -5
rg "HEAP_SIZE" debug.log | tail -5

Find Exceptions

# Find all exceptions
rg "EXCEPTION_THROWN|FATAL_ERROR" debug.log

# Get stack traces
rg -A 10 "FATAL_ERROR" debug.log

Find Slow Operations

# Extract all timing info
rg "\[\d+\]ms" debug.log | sort -t'[' -k2 -rn | head -20

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Developer Console Analysis

For quick checks directly in Salesforce:

Query Plan Tool

1. Open Developer Console
2. Query Editor tab
3. Click "Query Plan" checkbox
4. Run your query
5. Review selectivity and cost

Log Inspector

1. Open Developer Console
2. Debug → Open Execute Anonymous Window
3. Run code to generate log
4. Select log in "Logs" tab
5. Debug → View Log Panels

Useful Panels:

• Execution Overview: Summary of operations
• Timeline: Visual execution flow
• Stack Tree: Call hierarchy
• Database: SOQL/DML details

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Quick Reference: What to Look For

Problem	What to Search	Pattern
SOQL in Loop	SOQL_EXECUTE_BEGIN	Same query repeated many times
DML in Loop	DML_BEGIN	Same DML repeated many times
Slow Query	SOQL_EXECUTE_END	Large row count
CPU Issue	CPU_TIME	Approaching 10,000ms
Heap Issue	HEAP_SIZE	Approaching 6,000,000
Exception	EXCEPTION_THROWN	Stack trace

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Comparison: Analysis Tools

Tool	Pros	Cons	Best For
Apex Log Analyzer	Visual, free, flame charts	Requires VS Code	Deep performance analysis
Developer Console	Built-in, no install	Limited visualization	Quick checks
SF CLI + grep	Scriptable, fast	No visualization	CI/CD, automation
Salesforce Inspector	Browser-based	Limited log analysis	Quick org exploration

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Related Resources

• debug-log-reference.md - Log event types
• benchmarking-guide.md - Performance testing
• cli-commands.md - SF CLI reference