TELCODOCS-1512: Adding content for new feature that enables defining shared CPUs in the performance profile

Author: rohennes

_topic_maps/_topic_map.yml

@@ -2709,6 +2709,9 @@ Topics:
 - Name: Creating a performance profile
   File: cnf-create-performance-profiles
   Distros: openshift-origin,openshift-enterprise
+- Name: Shared CPUs for peripheral workload tasks
+  File: cnf-shared-cpu-for-workloads
+  Distros: openshift-origin,openshift-enterprise
 - Name: Workload partitioning
   File: enabling-workload-partitioning
   Distros: openshift-origin,openshift-enterprise

scalability_and_performance/cnf-shared-cpu-for-workloads.adoc

@@ -0,0 +1,27 @@
+:_mod-docs-content-type: ASSEMBLY
+[id="cnf-shared-cpu-for-workloads"]
+= Shared CPUs for peripheral workload tasks
+include::_attributes/common-attributes.adoc[]
+:context: cnf-shared-cpu-for-workloads
+
+toc::[]
+
+Within high-performance workloads, some lightweight application tasks can occupy valuable CPU resources. For example, log printing or configuration processing can occupy an isolated core that would be better used for integral, resource-instensive workload demands. You can increase workload performance, and more efficiently use CPU resources, by moving these lightweight tasks to a set of shared CPUs. 
+
+You can define a set of shared CPUs by using a performance profile. Shared CPUs are a part of the kublet's `reservedSystemCpus` pool. When you enable shared CPUs, the `reservedSystemCpus` pool is internally partitioned into a `shared` CPU pool and a `reserved` CPU pool. Shared CPUs can process system housekeeping tasks and lightweight workload tasks. In contrast, reserved CPUs only process system housekeeping tasks. This ensures no added latency in system housekeeping tasks, while minor latency in peripheral workload tasks is acceptable. 
+
+[NOTE]
+====
+System housekeeping tasks can only run on shared CPUs when workload partitioning is disabled.
+====
+
+
+include::modules/cnf-about-the-profile-creator-tool.adoc[leveloffset=+1]
+
+
+
+[id="{context}-additional-resources"]
+[role="_additional-resources"]
+== Additional resources
+* For more information about the `must-gather` tool,
+see xref:../support/gathering-cluster-data.adoc#nodes-nodes-managing[Gathering data about your cluster].