ocaml-mem_usage

A cross-platform OCaml module for reporting memory usage, with a focus on distinguishing private memory (allocated by the process itself) from shared memory (e.g., shared libraries, memory-mapped files).

Overview

The module reports both system-wide and per-process memory statistics:

Field	Description
total_physical_memory	Total RAM installed on the system
total_virtual_memory	Total virtual memory (RAM + swap)
total_used_physical_memory	RAM currently in use system-wide
total_used_virtual_memory	Virtual memory in use system-wide
process_virtual_memory	Virtual address space of the process
process_physical_memory	Resident set size (RSS) - pages in RAM
process_private_memory	Private pages unique to this process (USS)
process_swapped_memory	Process pages swapped to disk

The key metric is process_private_memory which represents memory that would be freed if this process terminates, excluding shared libraries and other shared mappings.

Supported Platforms

• Linux
• macOS
• Windows
• FreeBSD

Example

let () =
  let info = Mem_usage.info () in
  Printf.printf "Process private memory: %s\n"
    (Mem_usage.prettify_bytes ~binary:true info.process_private_memory)

Output:

Process private memory: 1.25 MiB

Installation

opam install mem_usage

To install from source:

git clone https://github.com/savonet/ocaml-mem_usage.git
cd ocaml-mem_usage
opam install .

Documentation

API documentation

License

MIT