sysinfo.cr

Cross-platform system & process memory info for Crystal — a small port of the Rust sysinfo crate's surface:

• Sysinfo.memory — global RAM: total_kb / available_kb / used_kb / percent
• Sysinfo.refresh_processes — rebuild the pid / parent / RSS snapshot
• Sysinfo.processes — the last snapshot (Sysinfo::Process entries)
• Sysinfo.process_tree_memory_kb(pid) — RSS of a process and all its descendants (what a terminal tab actually uses: the shell plus its compilers/servers/agents), cycle-safe

The library is synchronous, like the Rust crate — callers decide when and where to refresh (h2term hides it on a background fiber).

Backends

On Linux /proc's top level lists only thread-group leaders, so per-thread RSS can never be double-counted (upstream sysinfo has to filter thread entries explicitly). On macOS, RSS is readable only for processes the current uid may signal; others report 0 KB.

Use

require "sysinfo"

if mem = Sysinfo.memory
  puts "RAM #{mem.used_kb // 1024}/#{mem.total_kb // 1024} MB (#{mem.percent}%)"
end

Sysinfo.refresh_processes
Sysinfo.process_tree_memory_kb(Process.pid) # => whole tree RSS in KB

Test

crystal spec