[8.10] Add docs for gomaxprops option (backport #416)

docs/en/ingest-management/elastic-agent/install-elastic-agent.asciidoc

@@ -65,3 +65,30 @@ The {agent} used the default policy, running the system integration and self-mon
 | **RSS Mem Size** | 400 MB
 |===
 Adding integrations will increase the memory used by the agent and its processes.
+
+[discrete]
+=== Limiting CPU usage
+
+If you need to limit the amount of CPU consumption you can use the `agent.limits.go_max_procs` configuration option. This parameter limits the number of operating system threads that can be executing Go code simultaneously in each Go process. The `agent.limits.go_max_procs` option accepts an integer value not less than `0`, which is the default value that stands for "all available CPUs".
+
+The `agent.limits.go_max_procs` limit applies independently to the agent and each underlying Go process that it supervises. For example, if {agent} is configured to supervise two {beats} with `agent.limits.go_max_procs: 2` in the policy, then the total CPU limit is six, where each of the three processes (one {agent} and two {Beats}) may execute independently on two CPUs.
+
+This setting is similar to the {beats} {filebeat-ref}/configuration-general-options.html#_max_procs[`max_procs`] setting. For more detail, refer to the link:https://pkg.go.dev/runtime#GOMAXPROCS[GOMAXPROCS] function in the Go runtime documentation.
+
+To enable `agent.limits.go_max_procs`, run a <<fleet-api-docs,{fleet} API>> request from the {kib} {kibana-ref}/console-kibana.html[Dev Tools console] to override your current {agent} policy and add the `go_max_procs` parameter. For example, to limit Go processes supervised by {agent} to two operating system threads each, run:
+
+[source,shell]
+--
+PUT kbn:/api/fleet/agent_policies/<policy-id>
+{
+  "name": "<policy-name>",
+  "namespace": "default",
+  "overrides": {
+    "agent": {
+      "limits": {
+        "go_max_procs": 2
+      }
+    }
+  }
+}
+--