Numa node detection

Numa node detection

[Pico Geyer]

Good day,

I've started testing a dpdk application on a new system with more
cores than I usually do.
I'm running into an error relating to the number of numa nodes on the system.
We use the socket-mem argument to allocate just the right amount of
huge pages on each numa node (socket?).

lscpu output looks as follows:
lscpu
Architecture:          x86_64
<snip>
CPU(s):                160
On-line CPU(s) list:   0-159
Thread(s) per core:    2
Core(s) per socket:    20
Socket(s):             4
NUMA node(s):          8
Vendor ID:             GenuineIntel
CPU family:            6
Model:                 85
Model name:            Intel(R) Xeon(R) Gold 6248 CPU @ 2.50GHz
<snip>
NUMA node0 CPU(s):     0-9,80-89
NUMA node1 CPU(s):     10-19,90-99
NUMA node2 CPU(s):     20-29,100-109
NUMA node3 CPU(s):     30-39,110-119
NUMA node4 CPU(s):     40-49,120-129
NUMA node5 CPU(s):     50-59,130-139
NUMA node6 CPU(s):     60-69,140-149
NUMA node7 CPU(s):     70-79,150-159

So my current scripting mechanism would use the following --socket-mem
argument to start a dpdk instance on the first numa node:
app_name <other_args> --socket-mem=570,0,0,0,0,0,0,0  --core 1

On this system, I now get:
EAL: Detected 128 lcore(s)
EAL: Detected 4 NUMA nodes
EAL: invalid parameters for --socket-mem

I suppose dkdk is looking at the number of sockets and I've been using
number of numa nodes in my scripts.

However it's not clear to me how to simply fix the issue since
hugepage allocation is done on the level of numa nodes.

Also eal init seems to say it detected 4 numa nodes when the system
has 8, at least according to lscpu output.

I'm on dpdk 20.11 if that's pertinent.

Thanks in advance for any suggestions.
Pico