Update Topology Manager documentation to include the scope feature

Signed-off-by: Krzysztof Wiatrzyk <k.wiatrzyk@samsung.com>

content/en/docs/tasks/administer-cluster/topology-manager.md

@@ -24,7 +24,7 @@ _Topology Manager_ is a Kubelet component that aims to co-ordinate the set of co
 
 
 
-## {{% heading "prerequisites" %}}
+## {{% heading "prerequisites" %}}
 
 
 {{< include "task-tutorial-prereqs.md" >}} {{< version-check >}}
@@ -51,6 +51,23 @@ The hint is then stored in the Topology Manager for use by the *Hint Providers*
 
 Support for the Topology Manager requires `TopologyManager` [feature gate](/docs/reference/command-line-tools-reference/feature-gates/) to be enabled. It is enabled by default starting with Kubernetes 1.18.
 
+### Topology Manager Scopes
+
+The Topology Manager can deal with the alignment of resources in a couple of distinct scopes:
+
+* `container` (default)
+* `pod`
+
+Either option can be selected at a time of the kubelet startup, with `--topology-manager-scope` flag.
+
+### container scope
+
+This is a default scope. When container scope is set, the Topology Manager makes the resource alignment decision for each container of the pod separately.
+
+### pod scope
+
+When `pod` scope is set, the kubelet makes the resource alignment decision for the entire pod at once. Resource demand for the pod is calculated with [effective requests/limits](/docs/concepts/workloads/pods/init-containers/#resources), which is greater of the two: the sum of all app containers request and maximum of init containers request for a resource.
+
 ### Topology Manager Policies
 
 The Topology Manager currently:
@@ -73,6 +90,10 @@ There are four supported policies:
 * `restricted`
 * `single-numa-node`
 
+{{< note >}}
+If Topology Manager is configured with the **pod** scope, the container, which is considered by the policy, is reflecting requirements of the entire pod, and thus each container from the pod will result with **the same** resources assignment decision.
+{{< /note >}}
+
 ### none policy {#policy-none}
 
 This is the default policy and does not perform any topology alignment.