[PATCH v2 2/4] usertools/cpu_layout: print out NUMA nodes

[Robin Jarry]

Anatoly Burakov, Aug 16, 2024 at 14:16:
> In traditional NUMA case, NUMA nodes and physical sockets were used
> interchangeably, but there are cases where there can be multiple NUMA
> nodes per socket, as well as all CPU's being assigned NUMA node 0 even in
> cases of multiple sockets. Use sysfs to print out NUMA information.
>
> Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
> ---
>  usertools/cpu_layout.py | 35 ++++++++++++++++++++++++++++++-----
>  1 file changed, 30 insertions(+), 5 deletions(-)
>
> diff --git a/usertools/cpu_layout.py b/usertools/cpu_layout.py
> index be86f06938..e43bdbf343 100755
> --- a/usertools/cpu_layout.py
> +++ b/usertools/cpu_layout.py
> @@ -4,6 +4,7 @@
>  # Copyright(c) 2017 Cavium, Inc. All rights reserved.
>  
>  from typing import List, Set, Dict, Tuple
> +import glob

Can you keep the import sorted alphabetically?

>  
>  
>  def _range_expand(rstr: str) -> List[int]:
> @@ -26,11 +27,19 @@ def _read_sysfs(path: str) -> str:
>          return fd.read().strip()
>  
>  
> +def _read_numa_node(base: str) -> int:
> +    node_glob = f"{base}/node*"
> +    node_dirs = glob.glob(node_glob)
> +    if not node_dirs:
> +        return 0  # default to node 0
> +    return int(node_dirs[0].split("node")[1])

Maybe you could make this safer and more "python"-ic as follows:

def read_numa_node(base: str) -> int:
    for node in glob.iglob(f"{base}/node*"):
        match = re.match(r"^.*/node(\d+)$", node)
        if match:
            return int(match.group(1))
    return 0  # default to node 0

> +
> +
>  def _print_row(row: Tuple[str, ...], col_widths: List[int]) -> None:
>      first, *rest = row
>      w_first, *w_rest = col_widths
>      first_end = " " * 4
> -    rest_end = " " * 10
> +    rest_end = " " * 4
>  
>      print(first.ljust(w_first), end=first_end)
>      for cell, width in zip(rest, w_rest):
> @@ -50,6 +59,7 @@ def _main() -> None:
>      sockets_s: Set[int] = set()
>      cores_s: Set[int] = set()
>      core_map: Dict[Tuple[int, int], List[int]] = {}
> +    numa_map: Dict[int, int] = {}
>      base_path = "/sys/devices/system/cpu"
>  
>      cpus = _range_expand(_read_sysfs(f"{base_path}/online"))
> @@ -58,12 +68,14 @@ def _main() -> None:
>          lcore_base = f"{base_path}/cpu{cpu}"
>          core = int(_read_sysfs(f"{lcore_base}/topology/core_id"))
>          socket = int(_read_sysfs(f"{lcore_base}/topology/physical_package_id"))
> +        node = _read_numa_node(lcore_base)
>  
>          cores_s.add(core)
>          sockets_s.add(socket)
>          key = (socket, core)
>          core_map.setdefault(key, [])
>          core_map[key].append(cpu)
> +        numa_map[cpu] = node
>  
>      cores = sorted(cores_s)
>      sockets = sorted(sockets_s)
> @@ -73,24 +85,37 @@ def _main() -> None:
>  
>      print("cores = ", cores)
>      print("sockets = ", sockets)
> +    print("numa = ", sorted(set(numa_map.values())))
>      print()
>  
> -    # Core, [Socket, Socket, ...]
> -    heading_strs = "", *[f"Socket {s}" for s in sockets]
> +    # Core, [NUMA, Socket, NUMA, Socket, ...]
> +    heading_strs = "", *[v for s in sockets for v in ("", f"Socket {s}")]
>      sep_strs = tuple("-" * len(hstr) for hstr in heading_strs)
>      rows: List[Tuple[str, ...]] = []
>  
> +    prev_numa = None
>      for c in cores:
>          # Core,
>          row: Tuple[str, ...] = (f"Core {c}",)
>  
> -        # [lcores, lcores, ...]
> +        # assume NUMA changes symmetrically
> +        first_lcore = core_map[(0, c)][0]
> +        cur_numa = numa_map[first_lcore]
> +        numa_changed = prev_numa != cur_numa
> +        prev_numa = cur_numa
> +
> +        # [NUMA, lcores, NUMA, lcores, ...]
>          for s in sockets:
>              try:
>                  lcores = core_map[(s, c)]
> +                numa = numa_map[lcores[0]]
> +                if numa_changed:
> +                    row += (f"NUMA {numa}",)
> +                else:
> +                    row += ("",)
>                  row += (str(lcores),)
>              except KeyError:
> -                row += ("",)
> +                row += ("", "")
>          rows += [row]
>  
>      # find max widths for each column, including header and rows
> -- 
> 2.43.5