Analyzer lj-mem-realloc-distr

# Name

lj-mem-realloc-distr - Lua Memory Realloc Size Distribution

This analyzer monitors memory allocation and reallocation size distribution in LuaJIT-based applications such as OpenResty and Kong. It captures both new GC object allocations and memory reallocation events, tracking the target sizes being allocated. The histogram shows the distribution of allocation sizes, helping identify memory usage patterns and potential optimization opportunities in Lua memory management.

# Resource Category

Memory.

# 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-mem-realloc-distr -p PID

# trace a shell command directly
orxray analyzer run lj-mem-realloc-distr -c SHELL_CMD

# PGID is the process group ID or any process's PID within the target process
# group.
orxray analyzer run lj-mem-realloc-distr -p -PGID

# trace any processes started from the specified executable path.
orxray analyzer run lj-mem-realloc-distr --exe /path/to/exe/file

# Tracing Multiple Processes

Supported.

# Output Formats

• Histogram Bar Charts
• Plain Texts

# Output Example

{
  "data": [{
    "title": "Lua Memory Reallocation Size Distribution",
    "subtitle": "337 Calls (min: 24 bytes, avg: 426 bytes, max: 3072 bytes)",
    "type": "dist-bar",
    "ver": 1,
    "series": {
      "data": {
        "4": 0, "8": 0, "16": 28, "32": 105, "64": 130, "128": 20,
        "256": 12, "512": 4, "1024": 0, "2048": 38, "4096": 0, "8192": 0
      },
      "categoryUnit": "bytes",
      "categoryTitle": "Memory Size",
      "name": "Calls"
    },
    "summary": {"avg": 426, "max": 3072, "min": 24, "cnt": 337},
    "kind": "lj-mem-realloc-distr"
  }],
  "kind": "common"
}

# Author

The OpenResty Inc. Team.

# Copyright

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