Analyzer lj-c-on-cpu

# Name

lj-c-on-cpu - C-Land CPU Flame Graph for LuaJIT

This analyzer profiles CPU usage in C-land code execution within LuaJIT-based applications such as OpenResty and Kong. It captures stack traces from native C functions. The analyzer generates flame graphs that visualize CPU time distribution across C-level function calls, helping identify performance bottlenecks in native code execution.

# Resource Category

CPU.

# Application Type & Technical Stack

• OpenResty
• Kong
• APISIX

# Command Line Syntax

The analyzer can be invoked directly on the command-line via the orxray utility from the openresty-xray-cli software package.

Alternatively, the analyzer can also be invoked manually or automatically on the web console UI of OpenResty XRay (like on the Advanced web page).

# PID is the target process PID.
orxray analyzer run lj-c-on-cpu -p PID

# trace a shell command directly
orxray analyzer run lj-c-on-cpu -c SHELL_CMD

# PGID is the process group ID or any process's PID within the target process
# group.
orxray analyzer run lj-c-on-cpu -p -PGID

# trace any processes started from the specified executable path.
orxray analyzer run lj-c-on-cpu --exe /path/to/exe/file

# Tracing Multiple Processes

Supported.

# Output Formats

• Flame Graphs

# Author

The OpenResty Inc. Team.

# Copyright

Copyright (C) by OpenResty Inc. All rights reserved.