Downgrade warning for NUMA nodes without CPUs (valid Linux topology) #3828
Description
On my aarch64 architecture node (RaspberryPi) I get the following warning:
alloy[669]: ts=2026-01-24T22:30:39.860434727Z level=warn msg="Found node without any CPU, nodeDir: /sys/devices/system/node/node1, number of cpuDirs 0, err: <nil>" component_path=/ component_id=prometheus.exporter.cadvisor.integrations_cadvisor func=Warningf
I think the issue is that on ARM systems, Linux may expose NUMA node directories that only contain cpulist / cpumap files and no per-CPU directories.
I suggest to change the code from klog.Warning to a lower log level or to change the logic to also work with this cpu setup.
Additional info about this specific CPU:
$ uname -m
aarch64
$ cat /proc/cpuinfo | grep -m1 "CPU architecture"
CPU architecture: 8
$ ls -1d /sys/devices/system/node/node*
/sys/devices/system/node/node0
/sys/devices/system/node/node1
$ for n in /sys/devices/system/node/node*; do
> echo "== $n =="
> ls "$n" | grep '^cpu' || echo "(no CPUs)"
> done
== /sys/devices/system/node/node0 ==
cpu0
cpu1
cpu2
cpu3
cpulist
cpumap
== /sys/devices/system/node/node1 ==
cpulist
cpumap
$ for c in /sys/devices/system/cpu/cpu*/topology/physical_package_id; do
> echo "$c: $(cat "$c")"
> done
/sys/devices/system/cpu/cpu0/topology/physical_package_id: 0
/sys/devices/system/cpu/cpu1/topology/physical_package_id: 0
/sys/devices/system/cpu/cpu2/topology/physical_package_id: 0
/sys/devices/system/cpu/cpu3/topology/physical_package_id: 0
$ cat /sys/devices/system/cpu/cpu0/topology/numa_node
cat: /sys/devices/system/cpu/cpu0/topology/numa_node: No such file or directory