Use "requests" for CPU resources instead of limits

We now use a CPU request to ensure logging infrastructure pods are
not capped by default for CPU usage. It is still important to ensure
we have a minimum amount of CPU.

We keep the use of the variables *_cpu_limit so that the existing
behavior is maintained.

Note that we don't want to cap an infra pod's CPU usage by default,
since we want to be able to use the necessary resources to complete
it's tasks.

Bug 1501960 (https://bugzilla.redhat.com/show_bug.cgi?id=1501960)

4 files changed, 9 insertions, 8 deletions

diff --git a/roles/openshift_logging_eventrouter/README.md b/roles/openshift_logging_eventrouter/README.md
index da313d68b..611bdaee0 100644
--- a/roles/openshift_logging_eventrouter/README.md
+++ b/roles/openshift_logging_eventrouter/README.md
@@ -3,9 +3,9 @@ Event router
 
 A pod forwarding kubernetes events to EFK aggregated logging stack.
 
-- **eventrouter** is deployed to logging project, has a service account and its own role to read events
+- **eventrouter** is deployed to default project, has a service account and its own role to read events
 - **eventrouter** watches kubernetes events, marshalls them to JSON and outputs to its sink, currently only various formatting to STDOUT
-- **fluentd** picks them up and inserts to elasticsearch *.operations* index
+- **fluentd** ingests as logs from **eventrouter** container (as it would any other container), and writes them to the appropriate index for the **eventrouter**'s namespace (in the 'default' namespace, the *.operations* index is used)
 
 - `openshift_logging_install_eventrouter`: When 'True', eventrouter will be installed. When 'False', eventrouter will be uninstalled.
 
@@ -15,6 +15,6 @@ Configuration variables:
 - `openshift_logging_eventrouter_image_version`: The image version for the logging eventrouter. Defaults to 'latest'.
 - `openshift_logging_eventrouter_sink`: Select a sink for eventrouter, supported 'stdout' and 'glog'. Defaults to 'stdout'.
 - `openshift_logging_eventrouter_nodeselector`: A map of labels (e.g. {"node":"infra","region":"west"} to select the nodes where the pod will land.
-- `openshift_logging_eventrouter_cpu_limit`: The amount of CPU to allocate to eventrouter. Defaults to '100m'.
+- `openshift_logging_eventrouter_cpu_request`: The minimum amount of CPU to allocate to eventrouter. Defaults to '100m'.
 - `openshift_logging_eventrouter_memory_limit`: The memory limit for eventrouter pods. Defaults to '128Mi'.
 - `openshift_logging_eventrouter_namespace`: The namespace where eventrouter is deployed. Defaults to 'default'.
diff --git a/roles/openshift_logging_eventrouter/defaults/main.yaml b/roles/openshift_logging_eventrouter/defaults/main.yaml
index 34e33f75f..4c0350c98 100644
--- a/roles/openshift_logging_eventrouter/defaults/main.yaml
+++ b/roles/openshift_logging_eventrouter/defaults/main.yaml
@@ -4,6 +4,7 @@ openshift_logging_eventrouter_image_version: "{{ openshift_logging_image_version
 openshift_logging_eventrouter_replicas: 1
 openshift_logging_eventrouter_sink: stdout
 openshift_logging_eventrouter_nodeselector: ""
-openshift_logging_eventrouter_cpu_limit: 100m
+openshift_logging_eventrouter_cpu_limit: null
+openshift_logging_eventrouter_cpu_request: 100m
 openshift_logging_eventrouter_memory_limit: 128Mi
 openshift_logging_eventrouter_namespace: default
diff --git a/roles/openshift_logging_eventrouter/tasks/install_eventrouter.yaml b/roles/openshift_logging_eventrouter/tasks/install_eventrouter.yaml
index 8df7435e2..cbbc6a8ec 100644
--- a/roles/openshift_logging_eventrouter/tasks/install_eventrouter.yaml
+++ b/roles/openshift_logging_eventrouter/tasks/install_eventrouter.yaml
@@ -45,7 +45,7 @@
     params:
       IMAGE: "{{openshift_logging_eventrouter_image_prefix}}logging-eventrouter:{{openshift_logging_eventrouter_image_version}}"
       REPLICAS: "{{ openshift_logging_eventrouter_replicas }}"
-      CPU: "{{ openshift_logging_eventrouter_cpu_limit }}"
+      CPU: "{{ openshift_logging_eventrouter_cpu_request }}"
       MEMORY: "{{ openshift_logging_eventrouter_memory_limit }}"
       NAMESPACE: "{{ openshift_logging_eventrouter_namespace }}"
       SINK: "{{ openshift_logging_eventrouter_sink }}"
diff --git a/roles/openshift_logging_eventrouter/templates/eventrouter-template.j2 b/roles/openshift_logging_eventrouter/templates/eventrouter-template.j2
index ea1fd3efd..7fdf959d3 100644
--- a/roles/openshift_logging_eventrouter/templates/eventrouter-template.j2
+++ b/roles/openshift_logging_eventrouter/templates/eventrouter-template.j2
@@ -25,7 +25,7 @@ objects:
     metadata:
       name: logging-eventrouter
     data:
-      config.json: |- 
+      config.json: |-
         {
           "sink": "${SINK}"
         }
@@ -65,9 +65,9 @@ objects:
               imagePullPolicy: Always
               resources:
                 limits:
-                  memory: ${MEMORY} 
-                  cpu: ${CPU}
+                  memory: ${MEMORY}
                 requires:
+                  cpu: ${CPU}
                   memory: ${MEMORY}
               volumeMounts:
               - name: config-volume