OpenResty's Official Blog for Technologies & Products

tutorial flame-graph cpu profiling openresty-xray performance

Key Highlights
Other Important Updates

Key Highlights
Other Important Updates

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 17 mins read

Flame Graphs: How to Read a CPU Flame Graph and Find the Code Burning Your CPU

What is a flame graph: definition, axes, and the four rules
How to read a flame graph: plateaus, towers, hair, and self vs total
Three real production flame graphs: PHP preg_match, Go regexp.MustCompile, Erlang erts_pcre_exec
From 100% CPU to the culprit line: a four-step workflow with a per-stack routing table
How to get a flame graph for your stack
Icicle graphs, flame charts, and other variants
Can AI read flame graphs for you?

What is a flame graph: definition, axes, and the four rules
How to read a flame graph: plateaus, towers, hair, and self vs total
Three real production flame graphs: PHP preg_match, Go regexp.MustCompile, Erlang erts_pcre_exec
From 100% CPU to the culprit line: a four-step workflow with a per-stack routing table
How to get a flame graph for your stack
Icicle graphs, flame charts, and other variants
Can AI read flame graphs for you?

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 17 mins read

P99 Latency: Why Averages Lie, and How to Diagnose the Slowest 1%

openresty-xray p99 latency performance flame-graph

What is P99 latency?
P50 vs P95 vs P99: what each percentile tells you
Why average latency lies
Why is P99 latency high? A root-cause spectrum
How to diagnose high P99 latency
How to reduce P99 latency: fix what you found
Summary
Frequently Asked Questions

What is P99 latency?
P50 vs P95 vs P99: what each percentile tells you
Why average latency lies
Why is P99 latency high? A root-cause spectrum
How to diagnose high P99 latency
How to reduce P99 latency: fix what you found
Summary
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 14 mins read

Memory Leak Detection in Production: From RSS Curve to Source Line

openresty-xray memory tutorial

The Symptom: A Memory Curve That Only Goes Up
Memory Leak or Just High Memory Usage?
Four Leak Patterns with Real Root-Cause Chains
It Looks Like a Leak, but It Isn’t
How to Locate a Leak: Top-Down Layered Attribution
Why Traditional Tools Fall Short in Production
Frequently Asked Questions

The Symptom: A Memory Curve That Only Goes Up
Memory Leak or Just High Memory Usage?
Four Leak Patterns with Real Root-Cause Chains
It Looks Like a Leak, but It Isn’t
How to Locate a Leak: Top-Down Layered Attribution
Why Traditional Tools Fall Short in Production
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 11 mins read

Off-CPU Analysis: Four Root Causes Behind Low CPU Yet High Latency

openresty-xray off-cpu tutorial

What Is Off-CPU Time?
The Symptom: CPU Usage Won’t Climb, Yet Requests Are Queuing
Four Categories of Off-CPU Root Causes with Real-World Root-Cause Chains
How to Quantify Off-CPU Time
On-CPU + Off-CPU = Wall-Clock Time: The Bigger Picture and the Tool Ecosystem
FAQ

What Is Off-CPU Time?
The Symptom: CPU Usage Won’t Climb, Yet Requests Are Queuing
Four Categories of Off-CPU Root Causes with Real-World Root-Cause Chains
How to Quantify Off-CPU Time
On-CPU + Off-CPU = Wall-Clock Time: The Bigger Picture and the Tool Ecosystem
FAQ

OpenResty XRay Aug 3, 2026

OpenResty XRay Updated Aug 3, 2026 2 mins read

OpenResty XRay Version 26.7.15. Now Available

openresty-xray ai analyzer

Key Highlights
Other Important Updates

Key Highlights
Other Important Updates

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 5 mins read

OpenResty XRay AI Assistant: Making Every Piece of Analysis Data Speak

How Is It Different from Pasting a Report into ChatGPT?
Three Typical Scenarios
FAQ: Can AI Really Read a Flame Graph? How Reliable Is It?

How Is It Different from Pasting a Report into ChatGPT?
Three Typical Scenarios
FAQ: Can AI Really Read a Flame Graph? How Reliable Is It?

OpenResty XRay Sep 9, 2026

OpenResty XRay Updated Sep 9, 2026 4 mins read

OpenResty Private Libraries: High-Performance Lua & Nginx Modules

private-library openresty nginx lua openresty-xray

The Full Catalog
What’s Inside, by Scenario
How Licensing Works
FAQ

The Full Catalog
What’s Inside, by Scenario
How Licensing Works
FAQ

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 2 mins read

OpenResty XRay Version 26.5.11. Now Available

Key Highlights
Other Important Updates

Key Highlights
Other Important Updates

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 1 min read

OpenResty XRay Version 26.2.1. Now Available

openresty-xray ylang dynamic-tracing

Key Highlights
Stability and Usability Enhancements

Key Highlights
Stability and Usability Enhancements

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 13 mins read

How OpenResty XRay Enables Full-Stack Dynamic Tracing in Production

Where Do Existing Dynamic Tracing Frameworks Fall Short in Production?
How Did OpenResty XRay Rethink Dynamic Tracing at the Architecture Level?
What Is a Full-Stack Flame Graph and How Do You Use It to Diagnose Performance Bottlenecks?
How Is OpenResty XRay Expanding Its Observability Coverage Over Time?
Further Reading and Real-World Case Studie

Where Do Existing Dynamic Tracing Frameworks Fall Short in Production?
How Did OpenResty XRay Rethink Dynamic Tracing at the Architecture Level?
What Is a Full-Stack Flame Graph and How Do You Use It to Diagnose Performance Bottlenecks?
How Is OpenResty XRay Expanding Its Observability Coverage Over Time?
Further Reading and Real-World Case Studie

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Introduction to OpenResty XRay

openresty-xray nginx

Core Philosophy: A Tracing Engine Built for the Unknown
Turning Noise into Signal: How XRay Demystifies Production Issues
Empowering Engineering Teams in Cloud-Native Reality
Built on a Robust, Open Technological Foundatione
Real-World Success Stories

Core Philosophy: A Tracing Engine Built for the Unknown
Turning Noise into Signal: How XRay Demystifies Production Issues
Empowering Engineering Teams in Cloud-Native Reality
Built on a Robust, Open Technological Foundatione
Real-World Success Stories

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 9 mins read

Hunting Down a Silent Memory Leak in OpenResty Without a Reboot

case-study openresty-xray memory nginx

A Complete Dissection of a Production Memory Leak
Why Are These Problems Nearly Unsolvable?
A System Transformation
When Performance Issues Go Beyond Just Tools

A Complete Dissection of a Production Memory Leak
Why Are These Problems Nearly Unsolvable?
A System Transformation
When Performance Issues Go Beyond Just Tools

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 4 mins read

Nginx Reverse Proxy QPS Dropped 15x: A Missing upstream keepalive and an -O0 Debug Build

openresty-xray case-study lua nginx off-cpu

A 15x Slower Nginx Reverse Proxy — and No Errors in the Logs
Flame Graphs Expose a Connection Storm: The Missing upstream keepalive
The Remaining 10% Gap: Baseline Comparison Points to the Compiler
How an -O0 Debug Build Cost Us 10% of Performance

A 15x Slower Nginx Reverse Proxy — and No Errors in the Logs
Flame Graphs Expose a Connection Storm: The Missing upstream keepalive
The Remaining 10% Gap: Baseline Comparison Points to the Compiler
How an -O0 Debug Build Cost Us 10% of Performance

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 9 mins read

How We Pinpointed a 244ms Latency Spike in a 500k QPS OpenResty Gateway

openresty-xray qps p99 cpu

Latency Spikes and CPU Waste Hidden Beneath Healthy Averages
Troubleshooting OpenResty Latency Without Code Changes or Restarts
The Results: Latency Spikes Eliminated, 30% Lower CPU Usage
Frequently Asked Questions

Latency Spikes and CPU Waste Hidden Beneath Healthy Averages
Troubleshooting OpenResty Latency Without Code Changes or Restarts
The Results: Latency Spikes Eliminated, 30% Lower CPU Usage
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 11 mins read

How to Diagnose Java Memory Leaks in Production — Without Heap Dumps or Restarts

openresty-xray java memory

Why Full GCs Didn’t Reclaim the Heap: A Production Java Memory Leak
How to Diagnose a Java Memory Leak in Production Without a Heap Dump
How to Find a Java Memory Leak: A Reusable 3-Step Method
Why Use OpenResty XRay to Find Java Memory Leaks on a Live JVM?
FAQ

Why Full GCs Didn’t Reclaim the Heap: A Production Java Memory Leak
How to Diagnose a Java Memory Leak in Production Without a Heap Dump
How to Find a Java Memory Leak: A Reusable 3-Step Method
Why Use OpenResty XRay to Find Java Memory Leaks on a Live JVM?
FAQ

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 8 mins read

When a "Black Box" Plugin Consumes 45% CPU: How We Pinpointed Lua Line 93 Without Source Code

case-study openresty-xray rsa

When perf Meets the Black Box
From Sampling to Full-Stack Dynamic Tracing
Uncovering the Evidence Trail
From What happene to Why
Summary

When perf Meets the Black Box
From Sampling to Full-Stack Dynamic Tracing
Uncovering the Evidence Trail
From What happene to Why
Summary

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 2 mins read

OpenResty XRay Version 25.10.11 Now Available

case-study openresty-xray gzip cpu

Three Key Highlights
Enhanced Diagnostic Accuracy and Stability
Usability and Security Enhancements

Three Key Highlights
Enhanced Diagnostic Accuracy and Stability
Usability and Security Enhancements

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 9 mins read

Gzip CPU Usage: Why Compression Level 6 Consumed 54% of Server CPU

How Gzip Compression Consumed 54% of CPU in Production
Why Gzip CPU Usage Was So High: A Configuration-Level Diagnosis
Quantifying Gzip and Brotli CPU Overhead
From Guesswork to Data-Driven Compression Tuning

How Gzip Compression Consumed 54% of CPU in Production
Why Gzip CPU Usage Was So High: A Configuration-Level Diagnosis
Quantifying Gzip and Brotli CPU Overhead
From Guesswork to Data-Driven Compression Tuning

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 4 mins read

Nginx C++ Module Memory Leak: Root Cause in Production, No Restart

case-study openresty-xray nginx c++

The Production Challenge: A C++ Module Memory Leak You Can’t Debug With GDB
How the Flame Graph Pinpointed the Leaking Function in ngx_dubbo_module
From Reactive to Proactive: XRay’s New Approach to Troubleshooting
The OpenResty XRay Closed-Loop Approach

The Production Challenge: A C++ Module Memory Leak You Can’t Debug With GDB
How the Flame Graph Pinpointed the Leaking Function in ngx_dubbo_module
From Reactive to Proactive: XRay’s New Approach to Troubleshooting
The OpenResty XRay Closed-Loop Approach

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 4 mins read

Non-Invasive Java Profiler: Capture Method Arguments in Production Without a Java Agent

openresty-xray java probe

Why Non-Invasive Java Profiling Matters in Production
Hands-on Demo: Capturing Java Method Arguments in Production
How OpenResty XRay Differs from Common Java Profilers
Frequently Asked Questions

Why Non-Invasive Java Profiling Matters in Production
Hands-on Demo: Capturing Java Method Arguments in Production
How OpenResty XRay Differs from Common Java Profilers
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Automated Root Cause Analysis: How OpenResty XRay Pinpoints Failures Down to the Code Line

openresty-xray dynamic-tracing analyzer

Why More Observability Data Doesn’t Mean Faster Root Cause Analysis
How XRay’s Automated Root Cause Analysis Differs from Traditional Monitoring
Automated Root Cause Analysis in Action: Three Production Cases
FAQ

Why More Observability Data Doesn’t Mean Faster Root Cause Analysis
How XRay’s Automated Root Cause Analysis Differs from Traditional Monitoring
Automated Root Cause Analysis in Action: Three Production Cases
FAQ

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 5 mins read

Perl Memory Leak: From Several GB to 60MB with One Flame Graph

tutorial openresty-xray perl memory

Pinpointing Memory Leak Root Causes with a Flame Graph
Significant Optimization Achievements
Further Reading
Summary

Pinpointing Memory Leak Root Causes with a Flame Graph
Significant Optimization Achievements
Further Reading
Summary

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 10 mins read

Node.js Function Probe: Capture Live Function Arguments Without Changing Code

openresty-xray node.js

Why Trace Node.js Functions Without Modifying Code
How to Capture Node.js Function Arguments Without Modifying Code
How Teams Use Non-Invasive Node.js Probes in Production

Why Trace Node.js Functions Without Modifying Code
How to Capture Node.js Function Arguments Without Modifying Code
How Teams Use Non-Invasive Node.js Probes in Production

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 9 mins read

The Nginx Worker That Refused to Serve More Than 300 RPS: Traced to a 75ms Event-Loop Block

openresty-xray case-study lua nginx off-cpu

High Load but No Useful Work: CPU Contention from a Missing worker_cpu_affinity
How Blocking Lua I/O Calls Halted the Nginx Event Loop
Measuring File I/O Latency: Up to 1.5ms per Call
How Bad Was the Nginx Event-Loop Blocking? 43,952 Samples, a 75ms Worst Case
Frequently Asked Questions

High Load but No Useful Work: CPU Contention from a Missing worker_cpu_affinity
How Blocking Lua I/O Calls Halted the Nginx Event Loop
Measuring File I/O Latency: Up to 1.5ms per Call
How Bad Was the Nginx Event-Loop Blocking? 43,952 Samples, a 75ms Worst Case
Frequently Asked Questions

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 4 mins read

Double Bottleneck Concurrency? OpenResty XRay Multi-dimensional Analysis Solves Performance Challenges

case-study openresty-xray gzip cpu

Overall CPU Usage Analysis
In-depth Module Analysis
Analysis of Compression Strategies
Analysis Conclusions
Optimization Solutions

Overall CPU Usage Analysis
In-depth Module Analysis
Analysis of Compression Strategies
Analysis Conclusions
Optimization Solutions

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 10 mins read

Non-Invasive Node.js CPU Profiling with Flame Graphs

openresty-xray node.js memory cpu

High CPU Usage Issues in Node.js Applications
CPU Blocking Issues in Node.js Applications
Automated Sampling and Expert Analysis
Performance Impact and Overhead
Future Plans

High CPU Usage Issues in Node.js Applications
CPU Blocking Issues in Node.js Applications
Automated Sampling and Expert Analysis
Performance Impact and Overhead
Future Plans

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 11 mins read

Nginx Core Dump Analysis: Catch a Worker Process Crash at the First Scene

case-study openresty-xray undo core-dump memory nginx

The Case: Frequent Nginx Worker Process Crashes No Log Could Explain
Analyzing the Recording: Replaying the Crash Back to the First Scene
Root Cause: A Use-After-Free in Nginx’s Connection Lifecycle
Frequently Asked Questions

The Case: Frequent Nginx Worker Process Crashes No Log Could Explain
Analyzing the Recording: Replaying the Crash Back to the First Scene
Root Cause: A Use-After-Free in Nginx’s Connection Lifecycle
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 9 mins read

How UDB and OpenResty XRay Let You See Through the Entire Perl Code Execution Process

openresty-xray undo perl udb

What is UDB?
Hands-on: Analyzing Perl Application Call Stacks with OpenResty XRay and UDB
Why More Developers Are Choosing UDB?
Summary

What is UDB?
Hands-on: Analyzing Perl Application Call Stacks with OpenResty XRay and UDB
Why More Developers Are Choosing UDB?
Summary

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 9 mins read

UDB + OpenResty XRay: Unlocking the Mystery of OpenResty Application Performance

openresty-xray undo lua udb

How OpenResty XRay Enhances Efficiency with UDB
Hands-On: Analyzing OpenResty Lua Call Stacks with UDB and OpenResty XRay
Advantages of Time-Travel Debugging
Summary

How OpenResty XRay Enhances Efficiency with UDB
Hands-On: Analyzing OpenResty Lua Call Stacks with UDB and OpenResty XRay
Advantages of Time-Travel Debugging
Summary

OpenResty XRay Jul 23, 2026

OpenResty XRay Updated Jul 23, 2026 8 mins read

How to Debug File I/O in Java with Time-Travel Call Stacks

openresty-xray undo java udb

Where IDE Breakpoints and Coredumps Fall Short in Java File I/O
Reconstructing the Full Java Call Stack from a Native write() Syscall
Debug Java File I/O Step by Step with Time-Travel Replay
Frequently Asked Questions

Where IDE Breakpoints and Coredumps Fall Short in Java File I/O
Reconstructing the Full Java Call Stack from a Native write() Syscall
Debug Java File I/O Step by Step with Time-Travel Replay
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 4 mins read

Unveiling Python Code Execution with UDB

openresty-xray undo python udb

The Unique Value of UDB in Python Debugging
Enhancing Debugging Capabilities with OpenResty XRay
Real-World Example: Analyzing Python Network Request Call Stacks
Summary

The Unique Value of UDB in Python Debugging
Enhancing Debugging Capabilities with OpenResty XRay
Real-World Example: Analyzing Python Network Request Call Stacks
Summary

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 7 mins read

Tracing an LRU Cache Memory Leak in OpenResty — Down to the Cached SSL Certificates

case-study openresty-xray lru memory

Why a Low-Traffic OpenResty App Kept Leaking Memory
How We Traced the LRU Cache Memory Leak, Step by Step
The Result: From Unbounded Growth to Stable Memory

Why a Low-Traffic OpenResty App Kept Leaking Memory
How We Traced the LRU Cache Memory Leak, Step by Step
The Result: From Unbounded Growth to Stable Memory

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

Uneven Nginx Worker CPU Usage: Tracing a Missing reuseport Flag and a cjson Hotspot

tutorial openresty-xray customer-story case-study

The Symptom: Some Nginx Workers Maxed Out While Others Sat Idle
How OpenResty XRay Pinpointed the Root Causes
The Fix: Three Optimizations and Their Measured Gains
Summary: What OpenResty XRay Found in Minutes
Frequently Asked Questions
What is OpenResty XRay

The Symptom: Some Nginx Workers Maxed Out While Others Sat Idle
How OpenResty XRay Pinpointed the Root Causes
The Fix: Three Optimizations and Their Measured Gains
Summary: What OpenResty XRay Found in Minutes
Frequently Asked Questions
What is OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 9 mins read

The Swiss Army Knife for Dynamic Tracing, How Ylang Tames Complexity

Industry Pain Point: Why We Desperately Need a New Tracing Language
The Core Tech: What Makes Y Language a Game-Changer?
Ylang Syntax: The Familiarity of C, The Power of Advanced Tracing
Killer Applications: Solving Problems Beyond the Reach of Traditional Tools
Universal Platform Support: Y Lang Goes Everywhere
Compiler Wizardry: Forging a Superior Language with Superior Tools

Industry Pain Point: Why We Desperately Need a New Tracing Language
The Core Tech: What Makes Y Language a Game-Changer?
Ylang Syntax: The Familiarity of C, The Power of Advanced Tracing
Killer Applications: Solving Problems Beyond the Reach of Traditional Tools
Universal Platform Support: Y Lang Goes Everywhere
Compiler Wizardry: Forging a Superior Language with Superior Tools

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 4 mins read

Major Breakthrough for OpenResty XRay: Non-Intrusive Analysis of Java Application Memory & Envoy Lua Performance

Gain Complete Insight into Java Application Memory, Non-Intrusively
Unlocking the Lua Performance Black Box Inside Envoy
The Road Ahead

Gain Complete Insight into Java Application Memory, Non-Intrusively
Unlocking the Lua Performance Black Box Inside Envoy
The Road Ahead

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 10 mins read

Why Dynamic Tracing is the Future of Production Troubleshooting

The Unseen Crisis in Modern Software
Why Traditional Tools Are Failing
Dynamic Tracing: The New Paradigm for Troubleshooting
The OpenResty XRay Difference
From Firefighting to True Observability

The Unseen Crisis in Modern Software
Why Traditional Tools Are Failing
Dynamic Tracing: The New Paradigm for Troubleshooting
The OpenResty XRay Difference
From Firefighting to True Observability

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 9 mins read

Deep Dive into Dynamic Tracing Technology: How OpenResty XRay Revolutionizes Problem Diagnosis

Dynamic Tracing: A Powerful Tool for Solving Complex System Issues
Why Choose OpenResty XRay?
Product Focus: XRay Applications in Real-World Scenarios
Common Misconceptions and FAQs: What You Might Want to Know About Dynamic Tracing

Dynamic Tracing: A Powerful Tool for Solving Complex System Issues
Why Choose OpenResty XRay?
Product Focus: XRay Applications in Real-World Scenarios
Common Misconceptions and FAQs: What You Might Want to Know About Dynamic Tracing

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 7 mins read

The Next Stop for Observability: How OpenResty XRay Redefines Problem Troubleshooting

Why is Problem Troubleshooting Becoming Increasingly Difficult in Modern Software Architecture?
Trend Insights: The Future of Observability Technology
How Does Dynamic Tracing Technology Break Through Abstraction Layers?
Use Case: Real-time Statistics of Plugin Resource Consumption in Production Kong Services
Conclusion

Why is Problem Troubleshooting Becoming Increasingly Difficult in Modern Software Architecture?
Trend Insights: The Future of Observability Technology
How Does Dynamic Tracing Technology Break Through Abstraction Layers?
Use Case: Real-time Statistics of Plugin Resource Consumption in Production Kong Services
Conclusion

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 7 mins read

Traditional Methods vs. Dynamic Tracing: A Revolution in Efficiency and Control

A Revolution in Efficiency and Control
Dynamic Tracing: X-Ray Vision for Your Systems
From Flame Graphs to System Panorama
Why Choose OpenResty XRay?
The Future of Observability: New Frontiers in Dynamic Tracing

A Revolution in Efficiency and Control
Dynamic Tracing: X-Ray Vision for Your Systems
From Flame Graphs to System Panorama
Why Choose OpenResty XRay?
The Future of Observability: New Frontiers in Dynamic Tracing

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 9 mins read

Why is Dynamic Tracing Difficult to Implement? How Does OpenResty XRay Break Through?

tutorial ylang openresty-xray analyzer

Why is Problem Troubleshooting Becoming Increasingly Difficult in Modern Software Architecture?
Trend Insights: The Future of Observability Technology
How Does Dynamic Tracing Technology Break Through Abstraction Layers?
Use Case: Real-time Statistics of Plugin Resource Consumption in Production Kong Services
Conclusion

Why is Problem Troubleshooting Becoming Increasingly Difficult in Modern Software Architecture?
Trend Insights: The Future of Observability Technology
How Does Dynamic Tracing Technology Break Through Abstraction Layers?
Use Case: Real-time Statistics of Plugin Resource Consumption in Production Kong Services
Conclusion

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

From Black Box to White Box: OpenResty XRay Makes System Issues Nowhere to Hide

tutorial openresty-xray

A Dynamic Tracing Tool That Turns Black Boxes into White Boxes
Comprehensive Multi-dimensional Analysis Capabilities
Real-World Case Studies
Product Vision

A Dynamic Tracing Tool That Turns Black Boxes into White Boxes
Comprehensive Multi-dimensional Analysis Capabilities
Real-World Case Studies
Product Vision

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 5 mins read

OpenResty XRay Empowers LLVM clang Performance Optimization Practices

tutorial openresty-xray

What is LLVM/clang
OpenResty XRay Analysis Process
Optimization Implementation and Results
Conclusion

What is LLVM/clang
OpenResty XRay Analysis Process
Optimization Implementation and Results
Conclusion

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 5 mins read

Self-Optimization: The Performance Evolution of OpenResty XRay

tutorial openresty-xray

Challenges and Pain Points
OpenResty XRay’s Self-Analysis Process
Remarkable Optimization Results
Technical Insights and Business Value
Conclusion

Challenges and Pain Points
OpenResty XRay’s Self-Analysis Process
Remarkable Optimization Results
Technical Insights and Business Value
Conclusion

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 5 mins read

OpenResty XRay Helps Boost Script Performance by 44 Times

From Bottleneck Discovery to Significant Speed Improvement
How OpenResty XRay Works
Comparison with Traditional Methods

From Bottleneck Discovery to Significant Speed Improvement
How OpenResty XRay Works
Comparison with Traditional Methods

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 4 mins read

Cross-Media Data Structure Drift: OpenResty XRay Enables 20x Performance Improvement

tutorial openresty-xray data-structure-drift

Performance Challenges and Breakthroughs
Practical Significance of 20x Performance Improvement
Future Outlook

Performance Challenges and Breakthroughs
Practical Significance of 20x Performance Improvement
Future Outlook

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 5 mins read

From OOM to O(1): The Implementation Path of Streaming JSON Parser

tutorial openresty-xray json

Differences between JSONL format and traditional JSON
Solution
Continuous optimization
Technical insights
verification

Differences between JSONL format and traditional JSON
Solution
Continuous optimization
Technical insights
verification

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 5 mins read

From Days to Hours: How OpenResty XRay Accelerated the Linux shred Tool by Dozens of Times

openresty-xray linux shred

Problem Analysis
OpenResty XRay Practical Results
Optimization Process
Application Value

Problem Analysis
OpenResty XRay Practical Results
Optimization Process
Application Value

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 4 mins read

Case Study: OpenResty XRay Doubles Ylang Compiler Performance

tutorial ylang openresty-xray analyzer

Case Study: OpenResty XRay Doubles Ylang Compiler Performance
Significant Optimization Results
Ylang Language: The Ideal Tool for Dynamic Tracing
A Model of Technical Synergy
Further Reading

Case Study: OpenResty XRay Doubles Ylang Compiler Performance
Significant Optimization Results
Ylang Language: The Ideal Tool for Dynamic Tracing
A Model of Technical Synergy
Further Reading

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 10 mins read

Java Application Profiling: CPU, Off-CPU & Disk I/O Without Safepoint Bias

openresty-xray java memory cpu

Profiling Java CPU hotspots with flame graphs
Off-CPU Java profiling: lock contention and blocking analysis
Java disk I/O profiling: tracing file and socket writes
OpenJDK 8/11/17/21 application profiling support
Automated sampling and expert analysis
Performance impact and overhead
FAQ

Profiling Java CPU hotspots with flame graphs
Off-CPU Java profiling: lock contention and blocking analysis
Java disk I/O profiling: tracing file and socket writes
OpenJDK 8/11/17/21 application profiling support
Automated sampling and expert analysis
Performance impact and overhead
FAQ

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

OpenResty XRay Mobile Apps: Monitor and Troubleshoot Your Apps from Android & iOS

tutorial openresty-xray mobile app

Download and install OpenResty XRay for Android
Sign into OpenResty XRay
Automatic analysis report
View the performance chart data on the dashboard page
Guided analysis feature
Frequently asked questions
What is OpenResty XRay

Download and install OpenResty XRay for Android
Sign into OpenResty XRay
Automatic analysis report
View the performance chart data on the dashboard page
Guided analysis feature
Frequently asked questions
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 26 mins read

The Wonderland of Dynamic Tracing (Part 1 of 3)

dynamic-tracing openresty-xray

Dynamic Tracing
What It Is
Too Good to be True?
How it Works
Still Having Doubts?
The Advantages of Dynamic Tracing
DTrace
SystemTap
DTrace and SystemTap
Applications of SystemTap in Production

Dynamic Tracing
What It Is
Too Good to be True?
How it Works
Still Having Doubts?
The Advantages of Dynamic Tracing
DTrace
SystemTap
DTrace and SystemTap
Applications of SystemTap in Production

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 15 mins read

The Wonderland of Dynamic Tracing (Part 2 of 3)

dynamic-tracing openresty-xray

Flame Graphs
Methodology
Knowledge Is Power
Open-Source and Debug Symbols

Flame Graphs
Methodology
Knowledge Is Power
Open-Source and Debug Symbols

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 6 mins read

The Wonderland of Dynamic Tracing (Part 3 of 3)

dynamic-tracing openresty-xray

Dynamic Tracing Support in Linux Kernels
Hardware Tracing
Analyze Remains of Dead Process
Traditional Debugging Technologies
A Messy World of Debugging
OpenResty XRay

Dynamic Tracing Support in Linux Kernels
Hardware Tracing
Analyze Remains of Dead Process
Traditional Debugging Technologies
A Messy World of Debugging
OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 8 mins read

How a Single "0" Took Down Bilibili — Every Server at 100% CPU, and Reboots Didn't Help

dynamic-tracing openresty-xray bilibili

The Platform Behind Hundreds of Millions of Streams
The July 2021 Bilibili Outage: When Rebooting Doesn’t Help
Finding the Root Cause with CPU Flame Graphs
One Type Mismatch, Entire System Down

The Platform Behind Hundreds of Millions of Streams
The July 2021 Bilibili Outage: When Rebooting Doesn’t Help
Finding the Root Cause with CPU Flame Graphs
One Type Mismatch, Entire System Down

OpenResty XRay Aug 11, 2026

OpenResty XRay Updated Aug 11, 2026 3 mins read

Memory Reduced by 60%, OpenResty XRay Precisely Locates Problem Code, Quickly Completes Fixes and Deployment

tutorial ylang openresty-xray analyzer

High Memory Usage by Worker Processes
Analysis Process
Questions about Worker Process Memory Not Being Released

High Memory Usage by Worker Processes
Analysis Process
Questions about Worker Process Memory Not Being Released

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 5 mins read

Install OpenResty XRay’s Agents on Kubernetes cluster

tutorial openresty-xray kubernetes agent install

Logging in to the Console
Installing the Agent on Kubernetes cluster
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

Logging in to the Console
Installing the Agent on Kubernetes cluster
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 4 mins read

Install OpenResty XRay’s Agents on Amazon Linux via Package Bundles

tutorial openresty-xray amazon-linux2 agent install

Logging in to the Console
Installing the Agent via Bundle Packages
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

Logging in to the Console
Installing the Agent via Bundle Packages
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 5 mins read

Install OpenResty XRay’s Agents on Ubuntu via Deb Packages

tutorial openresty-xray ubuntu agent install

Logging in to the Console
Installing the Agent via Deb Packages
Checking the Agent Status and Logs
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

Logging in to the Console
Installing the Agent via Deb Packages
Checking the Agent Status and Logs
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 4 mins read

Install OpenResty XRay’s Agents on CentOS via RPM Packages

tutorial openresty-xray centos agent install

Logging in to the Console
Installing the Agent via RPM Packages
Checking the Agent Status and Logs
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

Logging in to the Console
Installing the Agent via RPM Packages
Checking the Agent Status and Logs
Configuring and Detecting Applications
Initiating Analyzers and Viewing Insights
Install Another Agent
What is OpenResty XRay

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 6 mins read

How to deploy the on-premises version of OpenResty XRay on Microsoft's Azure cloud

tutorial openresty-xray azure

Create a subscription and a resource group
Create the Azure Kubernetes service
Prepare the environment variables
Log in to Azure from the command line
Create the namespace and secret for Kubernetes
Create the Azure Disk
Update the configuration file for the persistent volume
Update the Kubernetes configuration file
Create the persistent volume
Deploy the Kubernetes service
Configure the application gateway

Create a subscription and a resource group
Create the Azure Kubernetes service
Prepare the environment variables
Log in to Azure from the command line
Create the namespace and secret for Kubernetes
Create the Azure Disk
Update the configuration file for the persistent volume
Update the Kubernetes configuration file
Create the persistent volume
Deploy the Kubernetes service
Configure the application gateway

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

Debugging High Disk I/O in Go Services on Linux

tutorial openresty-xray go disk-io

Identifying the Go process with high disk I/O
Tracing Go disk read and write code paths with flame graphs
Automatic disk I/O analysis and reports
What is OpenResty XRay
Frequently Asked Questions

Identifying the Go process with high disk I/O
Tracing Go disk read and write code paths with flame graphs
Automatic disk I/O analysis and reports
What is OpenResty XRay
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

How to Trace Go Panics in Production Without Restarting

tutorial openresty-xray go exceptions

How to detect and analyze exceptions inside live Go applications
Automatic analysis and reports
What is OpenResty XRay
FAQ

How to detect and analyze exceptions inside live Go applications
Automatic analysis and reports
What is OpenResty XRay
FAQ

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 7 mins read

Pinpointing CPU-Hottest Go Code Paths Inside Prometheus (using OpenResty XRay)

tutorial openresty-xray prometheus garbage-collection go

Problem: high CPU usage
Use the guided analysis feature of OpenResty XRay to spot the CPU-hottest Go code paths
Automatic analysis and reports
What is OpenResty XRay

Problem: high CPU usage
Use the guided analysis feature of OpenResty XRay to spot the CPU-hottest Go code paths
Automatic analysis and reports
What is OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 6 mins read

CockroachDB High CPU Usage: Profiling a Live Go Server with Flame Graphs

tutorial openresty-xray cpu profiling flame-graph go cockroachdb

Problem: CockroachDB high CPU usage
Find the most CPU-intensive Go code paths with guided analysis
Automatic CPU analysis and reports
What is OpenResty XRay

Problem: CockroachDB high CPU usage
Find the most CPU-intensive Go code paths with guided analysis
Automatic CPU analysis and reports
What is OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 7 mins read

Measuring the Performance Overhead of OpenResty XRay When Profiling Go Applications

tutorial openresty-xray go overhead

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 4 mins read

Dynamic-Tracing Custom Go Programs with Custom Ylang Analyzers (using OpenResty XRay)

tutorial openresty-xray ylang analyzer go

Insert two key-value Pairs into a Go Variable
Write a Customize Ylang Analyzer to Dynamically Trace the Go program
Test the Results
What is OpenResty XRay

Insert two key-value Pairs into a Go Variable
Write a Customize Ylang Analyzer to Dynamically Trace the Go program
Test the Results
What is OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 7 mins read

etcd High CPU Usage: Find the Hottest Go Code Paths with Flame Graphs

tutorial openresty-xray go cpu etcd

Symptom: etcd consuming over 70% of a CPU core
Use OpenResty XRay Guided Analysis to find the hottest Go code paths
Automatic etcd CPU monitoring and reports
What is OpenResty XRay

Symptom: etcd consuming over 70% of a CPU core
Use OpenResty XRay Guided Analysis to find the hottest Go code paths
Automatic etcd CPU monitoring and reports
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Go Off-CPU Analysis: Tracing a Running Process Stuck at 2% CPU to a Blocking Shell Call

tutorial openresty-xray go cpu

The symptom: Go service CPU usage stays low under load
Running off-CPU analysis on the live Go process with OpenResty XRay
Root cause: a blocking shell command at a single source line
Automatic analysis and reports

The symptom: Go service CPU usage stays low under load
Running off-CPU analysis on the live Go process with OpenResty XRay
Root cause: a blocking shell command at a single source line
Automatic analysis and reports

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Golang High CPU Usage: Regex Compilation Burned 36.8% of CPU Time

tutorial openresty-xray go cpu profiling regex flame-graph

Observing High CPU Usage in a Go Process
Profiling Go CPU Usage with OpenResty XRay
Automatic Monitoring and Reports
What is OpenResty XRay

Observing High CPU Usage in a Go Process
Profiling Go CPU Usage with OpenResty XRay
Automatic Monitoring and Reports
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Diagnosing High Disk I/O in Python Applications with XRay

tutorial openresty-xray python disk-io

Identifying the Python process with high disk I/O
Tracing Python disk read and write code paths with flame graphs
Automatic disk I/O analysis and reports
What is OpenResty XRay
Frequently Asked Questions

Identifying the Python process with high disk I/O
Tracing Python disk read and write code paths with flame graphs
Automatic disk I/O analysis and reports
What is OpenResty XRay
Frequently Asked Questions

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 3 mins read

Performance Impact of OpenResty XRay when Tracing Python Apps

tutorial openresty-xray python overhead

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

Python Memory Profiler: Find the Largest Objects Eating RAM Without Code Changes

tutorial openresty-xray python memory

Find which Python process is using the most memory
Profile Python memory with guided analysis: find the largest objects and their modules
Automatically monitor Python memory usage with scheduled reports
What is OpenResty XRay

Find which Python process is using the most memory
Profile Python memory with guided analysis: find the largest objects and their modules
Automatically monitor Python memory usage with scheduled reports
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Python Process Stuck at 8% CPU: Off-CPU Analysis Traces a Blocking subprocess.run Call

tutorial openresty-xray python off-cpu

The symptom: Python process CPU usage stays low under heavy requests
Find the blocking Python code paths with OpenResty XRay’s Guided Analysis
Automatic analysis and reports in the Insights page
FAQ
What is OpenResty XRay
About The Author

The symptom: Python process CPU usage stays low under heavy requests
Find the blocking Python code paths with OpenResty XRay’s Guided Analysis
Automatic analysis and reports in the Insights page
FAQ
What is OpenResty XRay
About The Author

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 8 mins read

Java Tomcat Slow Response Time: Pinpoint the Exact Slow Request with PCAP

openresty-xray java tomcat latency performance

Diagnose Tomcat slow response time by catching the exact slow request
Selective packet capture: filter by duration, status, and path
Per-request PCAP download for one specific slow request
Tell server-side latency from network delay
Works for Spring Boot apps with embedded Tomcat

Diagnose Tomcat slow response time by catching the exact slow request
Selective packet capture: filter by duration, status, and path
Per-request PCAP download for one specific slow request
Tell server-side latency from network delay
Works for Spring Boot apps with embedded Tomcat

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

How to Trace Perl Exceptions in Production Without Restarting

tutorial openresty-xray perl exceptions

How to detect and analyze exceptions inside Perl applications
Automatic analysis and reports
What is OpenResty XRay
FAQ

How to detect and analyze exceptions inside Perl applications
Automatic analysis and reports
What is OpenResty XRay
FAQ

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

Perl Process Stuck at 13% CPU: Off-CPU Flame Graphs Pinpoint a Blocking HTTP Call

tutorial openresty-xray perl off-cpu

The symptom: Perl process CPU usage stays low under heavy requests
Find the blocking Perl code paths with OpenResty XRay’s off-CPU flame graphs
Automatic analysis and reports in the Insights page
FAQ
What is OpenResty XRay
About The Author

The symptom: Perl process CPU usage stays low under heavy requests
Find the blocking Perl code paths with OpenResty XRay’s off-CPU flame graphs
Automatic analysis and reports in the Insights page
FAQ
What is OpenResty XRay
About The Author

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 7 mins read

Performance Overhead of OpenResty XRay when Tracing Perl Apps

tutorial openresty-xray perl overhead

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 6 mins read

Locate the Largest Memory Objects in a Live Perl Process

tutorial openresty-xray perl memory

Symptom: a Perl process using high memory in top
Profile the process with OpenResty XRay guided analysis to find the largest Perl objects
Trace the largest object back to its source file
Monitor Perl process memory automatically with Insights reports
FAQ
What is OpenResty XRay

Symptom: a Perl process using high memory in top
Profile the process with OpenResty XRay guided analysis to find the largest Perl objects
Trace the largest object back to its source file
Monitor Perl process memory automatically with Insights reports
FAQ
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Perl High CPU Usage: 100% CPU Traced to a Regex Hotspot with Flame Graphs

tutorial openresty-xray perl cpu profiling regex flame-graph dancer2

Observing 100% CPU Usage in a Perl Process
Profiling Perl CPU Usage with OpenResty XRay
Automatic Monitoring and Reports
What is OpenResty XRay

Observing 100% CPU Usage in a Perl Process
Profiling Perl CPU Usage with OpenResty XRay
Automatic Monitoring and Reports
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Why Your Rust Process Has High Disk I/O (and How to Find the Cause)

tutorial openresty-xray rust disk-io

Identifying the Rust process with high disk I/O
Tracing the hottest Rust disk write code paths with flame graphs
Automatic disk I/O analysis and reports
What is OpenResty XRay
Frequently Asked Questions

Identifying the Rust process with high disk I/O
Tracing the hottest Rust disk write code paths with flame graphs
Automatic disk I/O analysis and reports
What is OpenResty XRay
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

How to Trace Rust Panics in Production Without Restarting

tutorial openresty-xray rust exceptions

How to detect and analyze exceptions inside live Rust applications
Automatic analysis and reports
What is OpenResty XRay
FAQ

How to detect and analyze exceptions inside live Rust applications
Automatic analysis and reports
What is OpenResty XRay
FAQ

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

Tested in Production: The Performance Impact of OpenResty XRay When Tracing Rust Applications

tutorial openresty-xray rust overhead

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

What Happens to CPU, Memory, and Load During Profiling?
How Much Does Profiling Affect Throughput and Latency?
OpenResty XRay vs. Always-On APM Agents
FAQ

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 7 mins read

Rust CPU Profiling: Find the Hottest Code Paths in Sled with OpenResty XRay

tutorial openresty-xray cpu sled rust profiling flame-graph

The problem: a Sled-based cache service using over 100% CPU
Profile the running Rust process with Guided Analysis
Read the Rust CPU flame graph: the #1 hottest code path
The #2 hottest code path: get_inner and view_for_key
Automatic Rust CPU analysis reports
Frequently asked questions

The problem: a Sled-based cache service using over 100% CPU
Profile the running Rust process with Guided Analysis
Read the Rust CPU flame graph: the #1 hottest code path
The #2 hottest code path: get_inner and view_for_key
Automatic Rust CPU analysis reports
Frequently asked questions

OpenResty XRay Sep 18, 2026

OpenResty XRay Updated Sep 18, 2026 11 mins read

From AI Flame Graph Analysis to Verified Fixes: A Coding-Agent Optimization Loop with OpenResty XRay

openresty-xray ai analyzer cpu lua

Prerequisite: OpenResty XRay must already be installed on the target machine
Your coding agent isn’t short on intelligence—it’s short on runtime visibility
Three optimization rounds: 336 → 4,457 → 26,028 → 29,968 RPS
Lua + C, two perspectives: why you shouldn’t try to optimize writev
FAQ

Prerequisite: OpenResty XRay must already be installed on the target machine
Your coding agent isn’t short on intelligence—it’s short on runtime visibility
Three optimization rounds: 336 → 4,457 → 26,028 → 29,968 RPS
Lua + C, two perspectives: why you shouldn’t try to optimize writev
FAQ

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 7 mins read

Use C++ to Dynamic-Trace C++ Applications

stl c++ ebpf openresty-xray dynamic-tracing

Setting Up the Target C++ Program
Crafting the C++ (or Y++) Analyzer
Operationalizing the Target and Analyzer
Advancing Support for Complex C++ Applications
About the Debug Symbols

Setting Up the Target C++ Program
Crafting the C++ (or Y++) Analyzer
Operationalizing the Target and Analyzer
Advancing Support for Complex C++ Applications
About the Debug Symbols

OpenResty XRay Aug 20, 2026

OpenResty XRay Updated Aug 20, 2026 7 mins read

Erlang High CPU Usage: PCRE Regex Bottleneck Traced with Flame Graphs

tutorial openresty-xray erlang cpu profiling regex flame-graph beam-vm

Observing 200%+ CPU in an Erlang Process
Profiling Erlang CPU Usage with OpenResty XRay
C-Level Analysis: erts_pcre_exec and PCRE Backtracking
Why PCRE Regex Backtracking Is Expensive in the BEAM VM
Automatic Monitoring and Reports
FAQ: Erlang High CPU Usage
What is OpenResty XRay

Observing 200%+ CPU in an Erlang Process
Profiling Erlang CPU Usage with OpenResty XRay
C-Level Analysis: erts_pcre_exec and PCRE Backtracking
Why PCRE Regex Backtracking Is Expensive in the BEAM VM
Automatic Monitoring and Reports
FAQ: Erlang High CPU Usage
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Nginx 'No Debugging Symbols Found'? Rebuild Them Automatically with OpenResty XRay

tutorial openresty-xray debug-symbol nodwarf

Confirming Nginx Is Stripped and Debug Symbols Are Missing
Rebuild Missing Nginx Debug Symbols Automatically — No Recompile Needed
Continuous Analysis: Daily and Weekly Insights Reports
FAQ: nginx-dbg, recompiling, and profiling stripped binaries

Confirming Nginx Is Stripped and Debug Symbols Are Missing
Rebuild Missing Nginx Debug Symbols Automatically — No Recompile Needed
Continuous Analysis: Daily and Weekly Insights Reports
FAQ: nginx-dbg, recompiling, and profiling stripped binaries

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 7 mins read

Automatic Core Dump Analysis (using OpenResty XRay)

openresty-xray core-dump lua-backtrace luajit dynamic-tracing ebpf

Locate the core dump file from a crashed OpenResty/Nginx worker
Start automatic (guided) core dump analysis in OpenResty XRay
Read the signal, CPU registers, and C backtrace of the crash
Follow the Lua backtrace to the exact crashing line
Automatic Insights reports for online core dumps

Locate the core dump file from a crashed OpenResty/Nginx worker
Start automatic (guided) core dump analysis in OpenResty XRay
Read the signal, CPU registers, and C backtrace of the crash
Follow the Lua backtrace to the exact crashing line
Automatic Insights reports for online core dumps

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 6 mins read

Envoy CPU Profiling: Find Hot C++ Paths with Flame Graphs

tutorial openresty-xray cpu envoy flame-graph profiling dynamic-tracing

Scenario: Envoy Proxy Running at 90% CPU
Profile Envoy CPU with C++ Flame Graphs
Continuous CPU Monitoring with Automated Reports
What is OpenResty XRay
FAQ: Envoy CPU Profiling

Scenario: Envoy Proxy Running at 90% CPU
Profile Envoy CPU with C++ Flame Graphs
Continuous CPU Monitoring with Automated Reports
What is OpenResty XRay
FAQ: Envoy CPU Profiling

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 8 mins read

How to Diagnose 504 Gateway Timeout Errors in OpenResty & Nginx

tutorial openresty-xray 504 timeout

Confirm HTTP 504 gateway timeout errors in the OpenResty/Nginx access log
Diagnose the 504 root cause with OpenResty XRay Guided Analysis
Slow upstream, slow network link, or a too-short timeout setting
Automatic root-cause reports on the Insights page

Confirm HTTP 504 gateway timeout errors in the OpenResty/Nginx access log
Diagnose the 504 root cause with OpenResty XRay Guided Analysis
Slow upstream, slow network link, or a too-short timeout setting
Automatic root-cause reports on the Insights page

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Django Memory Profiler: Analyze Object-Level Memory Usage in a Live App

tutorial openresty-xray python memory django

Spot a high-memory Django process with ps
Profile the Django app’s memory usage with Guided Analysis
Read the flame graph: which Python module uses the most memory
Monitor Django memory usage automatically with Insights
What is OpenResty XRay

Spot a high-memory Django process with ps
Profile the Django app’s memory usage with Guided Analysis
Read the flame graph: which Python module uses the most memory
Monitor Django memory usage automatically with Insights
What is OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 7 mins read

llama.cpp CPU Usage: 400% CPU Traced to ggml Hot Functions

tutorial openresty-xray llm cpu generative-ai llama2 llama.cpp profiling ai

Running llama.cpp and Observing 400% CPU Usage
Profiling llama.cpp CPU Usage with OpenResty XRay
Findings: The Hottest C++ Code Paths
What is OpenResty XRay

Running llama.cpp and Observing 400% CPU Usage
Profiling llama.cpp CPU Usage with OpenResty XRay
Findings: The Hottest C++ Code Paths
What is OpenResty XRay

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 5 mins read

Two bugs in Linux kernels' tracing subsystem (found by OpenResty XRay)

openresty-xray dynamic-tracing linux-kernel bugs

Kernel deadlocks in user-space memory reading
Data races in x86 breakpoint insertion of the kernel
What is OpenResty XRay

Kernel deadlocks in user-space memory reading
Data races in x86 breakpoint insertion of the kernel
What is OpenResty XRay

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 6 mins read

Lua High CPU Usage: Find the Hottest Lua Code Path in Nginx/OpenResty

tutorial openresty-xray lua cpu flame-graph profiling

The symptom: an Nginx worker process using almost 100% CPU
Find the hottest Lua code path with Guided Analysis
Monitor Lua CPU usage automatically with Insights reports
Frequently asked questions

The symptom: an Nginx worker process using almost 100% CPU
Find the hottest Lua code path with Guided Analysis
Monitor Lua CPU usage automatically with Insights reports
Frequently asked questions

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 6 mins read

Kong Plugin High CPU Usage: A Hidden Lua Exception Traced with Flame Graphs

openresty-xray exceptions lua kong nginx cpu

The problem: Kong plugin high CPU usage under light traffic
Finding the CPU bottleneck with an OpenResty XRay flame graph
The result: Kong CPU usage cut from 80% to 50%

The problem: Kong plugin high CPU usage under light traffic
Finding the CPU bottleneck with an OpenResty XRay flame graph
The result: Kong CPU usage cut from 80% to 50%

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 8 mins read

Kong Plugin Memory and CPU Usage: Find the Top Consumer Online (OpenResty XRay)

openresty-xray kong nginx lua memory cpu

CPU usage among all Kong plugins in a server process
Memory usage among all Kong plugins in a server process
Extra overhead for the servers

CPU usage among all Kong plugins in a server process
Memory usage among all Kong plugins in a server process
Extra overhead for the servers

OpenResty XRay Aug 27, 2026

OpenResty XRay Updated Aug 27, 2026 6 mins read

TCP Packet Capture on Slow Connections: Tracing a 200ms Nginx Request Body Delay

openresty-xray latency network smart-packet-capture nginx

The Problem
Analysis: TCP Packet Capture on Slow Connections
Fully-automated analysis
What is OpenResty XRay

The Problem
Analysis: TCP Packet Capture on Slow Connections
Fully-automated analysis
What is OpenResty XRay

OpenResty XRay Aug 24, 2026

OpenResty XRay Updated Aug 24, 2026 8 mins read

Find Leaked Lua Tables: the registry / _LOADED (package.loaded) Reference Path in OpenResty XRay

openresty memory-leak openresty-xray case-study

How LuaJIT manages memory
OpenResty XRay’s command-line tools
A leaking Lua table example
Breaking down memory by LuaJIT GC object type
Reading the lj-gco-ref flame graph: registry, _LOADED, package.loaded
Fully-automated Lua memory leak analysis

How LuaJIT manages memory
OpenResty XRay’s command-line tools
A leaking Lua table example
Breaking down memory by LuaJIT GC object type
Reading the lj-gco-ref flame graph: registry, _LOADED, package.loaded
Fully-automated Lua memory leak analysis

OpenResty XRay Jun 26, 2026

OpenResty XRay Updated Jun 26, 2026 8 mins read

Real-Time Request Counting against Nginx Processes via YSQL

openresty-xray ysql nginx

How to install the run-ysql tool
Count total requests served in real time
Filter out specific requests
Using YSQL in the Web Console
True non-invasive tracing

How to install the run-ysql tool
Count total requests served in real time
Filter out specific requests
Using YSQL in the Web Console
True non-invasive tracing

OpenResty XRay Sep 10, 2026

OpenResty XRay Updated Sep 10, 2026 7 mins read

Lua io.popen Blocks Nginx's Event Loop: A 150x Throughput Fix

openresty-xray nginx lua off-cpu

The Problem: 130 req/sec
How OpenResty XRay Found the Blocking
Nonblocking Alternatives to io.popen
Results: 7x and 150x
FAQ

The Problem: 130 req/sec
How OpenResty XRay Found the Blocking
Nonblocking Alternatives to io.popen
Results: 7x and 150x
FAQ

OpenResty XRay Sep 10, 2026

OpenResty XRay Updated Sep 10, 2026 8 mins read

Nginx Memory Doubles After Reload? Here's Why (and the Fix)

openresty-xray reports cdn nginx memory-fragmentation

Challenges
Analyses
Solutions
Results

Challenges
Analyses
Solutions
Results

OpenResty XRay Sep 9, 2026

OpenResty XRay Updated Sep 9, 2026 11 mins read

Nginx Regex Performance: Find Slow Patterns with Dynamic Tracing

regex openresty-xray dynamic-tracing nginx

Prerequisites and Setup
Locate Slow Regex with CPU Flame Graphs
Performance After Regex Optimization
Limit PCRE Backtracking with lua_regex_match_limit
Non-Backtracking Engines: RE2 and OpenResty Regex
Lua Built-in Patterns as a Regex Alternative
Trace Regex Performance in Docker and Kubernetes
How the Dynamic-Tracing Tools Work
Tool Overhead: Zero Impact When Not Sampling
FAQ: Nginx Regex Performance

Prerequisites and Setup
Locate Slow Regex with CPU Flame Graphs
Performance After Regex Optimization
Limit PCRE Backtracking with lua_regex_match_limit
Non-Backtracking Engines: RE2 and OpenResty Regex
Lua Built-in Patterns as a Regex Alternative
Trace Regex Performance in Docker and Kubernetes
How the Dynamic-Tracing Tools Work
Tool Overhead: Zero Impact When Not Sampling
FAQ: Nginx Regex Performance

OpenResty XRay Sep 9, 2026

OpenResty XRay Updated Sep 9, 2026 9 mins read

Listing Loaded Lua Modules in OpenResty or Nginx Processes

ylua openresty-xray nginx lua dynamic-tracing

System Environment
Names of Loaded Lua Modules
Running Directly in the Web Console
Tracing Applications inside Containers
How The Tools are Implemented
The Overhead of the Tools

System Environment
Names of Loaded Lua Modules
Running Directly in the Web Console
Tracing Applications inside Containers
How The Tools are Implemented
The Overhead of the Tools

OpenResty XRay Sep 9, 2026

OpenResty XRay Updated Sep 9, 2026 13 mins read

Nginx High CPU Usage: Find Which Requests Consume the Most CPU

tutorial cpu nginx openresty-xray ysql

Prerequisites and Environment Setup
Find Which Request Hostname Uses the Most CPU
Find Which Request URI Uses the Most CPU
Digging Deeper: Why Some Hostnames Use More CPU
Running the Tools in the Web Console
Tracing Nginx CPU Usage Inside Containers
How the CPU Profiling Tools Work
The Overhead of the Profiling Tools
Frequently Asked Questions

Prerequisites and Environment Setup
Find Which Request Hostname Uses the Most CPU
Find Which Request URI Uses the Most CPU
Digging Deeper: Why Some Hostnames Use More CPU
Running the Tools in the Web Console
Tracing Nginx CPU Usage Inside Containers
How the CPU Profiling Tools Work
The Overhead of the Profiling Tools
Frequently Asked Questions

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 15 mins read

Ylang in Production: Container Tracing, Stack Unwinding & Core Dumps (Series Part 4)

Transparent Container Tracing
Efficient Stack Unwinding
Analyzing Dead Processes (Core Dumps)
Very Low Tracing Overhead
Standard Ylang Libraries & Tools
Network Filtering & Control
The Ylang Compiler’s Implementation
Operating System Support
Contributions to Open-Source Communities

Transparent Container Tracing
Efficient Stack Unwinding
Analyzing Dead Processes (Core Dumps)
Very Low Tracing Overhead
Standard Ylang Libraries & Tools
Network Filtering & Control
The Ylang Compiler’s Implementation
Operating System Support
Contributions to Open-Source Communities

OpenResty XRay Aug 6, 2026

OpenResty XRay Updated Aug 6, 2026 11 mins read

Ylang: Regex, Full Control Flow & Transparent Debug Symbol Handling (Series Part 3)

The Language Syntax (Continued)
- String Literals
- Built-in Regex Support
- Full Control-Flow Support
- Floating-Point Number Support
- Compared to Open-Source Toolchains
Transparent Debug Symbol Handling
- Debug Symbols: No Runtime Overhead
- Centralized Package Database
- Fuzzy Matching Debug Symbols

The Language Syntax (Continued)
- String Literals
- Built-in Regex Support
- Full Control-Flow Support
- Floating-Point Number Support
- Compared to Open-Source Toolchains
Transparent Debug Symbol Handling
- Debug Symbols: No Runtime Overhead
- Centralized Package Database
- Fuzzy Matching Debug Symbols

OpenResty XRay Aug 6, 2026

OpenResty XRay Updated Aug 6, 2026 15 mins read

Ylang Syntax: Probes, Tracer/Tracee Spaces & Built-in Data Types (Series Part 2)

The Language Syntax (Continued)
- Macros with Extensions
- Tracer and Tracee Spaces
- Probes
- Extended Variable Types

The Language Syntax (Continued)
- Macros with Extensions
- Tracer and Tracee Spaces
- Probes
- Extended Variable Types

OpenResty XRay Aug 28, 2026

OpenResty XRay Updated Aug 28, 2026 15 mins read

Ylang: A Dynamic Tracing Language for eBPF, SystemTap, GDB, and More (Part 1 of 4)