Java · OpenResty Official Blog

Java

OpenResty XRay Jul 22, 2026

OpenResty XRay Updated Jul 22, 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 Jul 22, 2026

OpenResty XRay Updated Jul 22, 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 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 Jul 22, 2026

OpenResty XRay Updated Jul 22, 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

Photo by Yichun Zhang

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 Jul 22, 2026

OpenResty XRay Updated Jul 22, 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

Photo by Yichun Zhang

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

Contact us