SysInfo

This package is the backend of ThreadPinning.jl. However, you may use it directly to obtain core information about the compute system at hand (number of physical cores, NUMA domains, etc.).

• Get a compact summary of the system (topology and key figures).
• Query various properties of the system, including the number of CPU-threads, physical CPU-cores, and NUMA domains.
• Supports identifying different CPU-core kinds (e.g. "efficiency core" and "performance cores").
• Two backends: Hwloc.jl and lscpu.
• Fake mode: Simulate being on a different system (useful in conjuction with ThreadPinningCore.jl's fake mode).

On a Perlmutter (NERSC) login node:

julia> using SysInfo

julia> sysinfo() # only exported function
Hostname:       login19
CPU(s):         2 x AMD EPYC 7713 64-Core Processor
CPU target:     znver3
Cores:          128 (256 CPU-threads due to 2-way SMT)
NUMA domains:   8 (16 cores each)

∘ CPU 1: 
        → 64 cores (128 CPU-threads due to 2-way SMT)
        → 4 NUMA domains
∘ CPU 2: 
        → 64 cores (128 CPU-threads due to 2-way SMT)
        → 4 NUMA domains

Detected GPUs:  1

julia> SysInfo.ncores() # programmatic access, public API but not exported
128

julia> SysInfo.ncputhreads()
256

julia> SysInfo.nsockets()
2

julia> SysInfo.nnuma()
8

On a Mac mini M1:

julia> sysinfo()
Hostname: 	pc2macmini.fritz.box
CPU(s): 	1 x Apple M1
CPU target:     apple-m1

∘ CPU 1:
	→ 8 cores (8 CPU-threads)
	→ 4 "efficiency cores", 4 "performance cores".
	→ 1 NUMA domain

SysInfo.jl uses Hwloc.jl as the source of truth. It also has a lscpu-based backend that can be used as a replacement or for consistency checks (at least on Linux).

See api.jl and the @public/export markers in SysInfo.jl.

We fake-run the test suite of this package on a bunch of interesting systems (e.g. with interesting CPUs or topologies). You can readily add your interesting system to the list, which helps us ensure that this package (as well as ThreadPinning.jl) is working on your system.

(Please only add your system if you think it is worth testing on.)

On the desired system, run

SysInfo.TestSystems.dump_current_system("NameOfYourSystem")

This will create a folder NameOfYourSystem in the current directory which you should then add to the testsystems directory of this repository (via a pull request).

Thank you in advance!