Optimize XMRig Mining on ARM64 Machines

Question

I have an ARM64 machine at 3GHz with 100+ cores and am only seeing 2000 H/s. Is there any optimization techniques I'm missing for XMRig? This is a fraction of the H/s I'm seeing on a 20 core Intel machine.

Console output:

miner    speed 10s/60s/15m 2183.2 2189.4 n/a H/s max 2263.2 H/s

L1d cache:           64K
L1i cache:           64K
L2 cache:            1024K
NUMA node0 CPU(s):   0-79
NUMA node1 CPU(s):   80-159

 * ABOUT        XMRig/6.15.1 gcc/8.4.1
 * LIBS         libuv/1.42.0 OpenSSL/1.1.1g hwloc/2.2.0
 * HUGE PAGES   supported
 * 1GB PAGES    unavailable
 * CPU          ARM Neoverse-N1 (2) 64-bit AES

Config:

{
  "algo": "rx/0",
  "api": {
    "id": null,
    "worker-id": null
  },
  "http": {
    "enabled": false,
    "host": "127.0.0.1",
    "port": 0,
    "access-token": null,
    "restricted": true
  },
  "av": 0,
  "autosave": false,
  "background": false,
  "colors": true,
  "cpu-affinity": null,
  "cpu-priority": null,
  "donate-level": 1,
  "huge-pages": true,
  "hw-aes": null,
  "log-file": null,
  "max-threads-hint": 75,
  "pools": [
    {
      "url": "pool.minexmr.com:443",
      "user": "xxxxxxxxxxxxx--removed",
      "pass": "x",
      "keepalive": true,
      "nicehash": false,
      "variant": -1,
      "tls": true,
      "tls-fingerprint": null,
      "daemon": false,
      "socks5": null,
      "self-select": null,
      "submit-to-origin": false
    }
  ],
  "print-time": 60,
  "retries": 5,
  "retry-pause": 5,
  "safe": false,
  "syslog": false,
  "threads": null
}

Answer 1

1. Your config looks old. Make sure you use the latest version of xmrig and generate a config at: https://xmrig.com/wizard
2. Just because you have "100+" cores doesn't mean you will get the highest hashrate trying to use them all. For the most efficient mining with RandomX you need 16 KiB of L1 cache, 256 KiB of L2 cache and 2 MiB of L3 cache per mining thread. So if you want to run 100 threads (1 per core), you need approximately 226 MiB of cache, which you probably don't have. Thus you need to determine how much cache you do have and work out how many threads you can use.