Add SwapStats to NodeStats, PodStats and ContainerStats

Signed-off-by: Itamar Holder <iholder@redhat.com>

staging/src/k8s.io/kubelet/pkg/apis/stats/v1alpha1/types.go

@@ -59,6 +59,9 @@ type NodeStats struct {
 	// Stats about the rlimit of system.
 	// +optional
 	Rlimit *RlimitStats `json:"rlimit,omitempty"`
+	// Stats pertaining to swap resources. This is reported to non-windows systems only.
+	// +optional
+	Swap *SwapStats `json:"swap,omitempty"`
 }
 
 // RlimitStats are stats rlimit of OS.
@@ -131,6 +134,9 @@ type PodStats struct {
 	// ProcessStats pertaining to processes.
 	// +optional
 	ProcessStats *ProcessStats `json:"process_stats,omitempty"`
+	// Stats pertaining to swap resources. This is reported to non-windows systems only.
+	// +optional
+	Swap *SwapStats `json:"swap,omitempty"`
 }
 
 // ContainerStats holds container-level unprocessed sample stats.
@@ -159,6 +165,9 @@ type ContainerStats struct {
 	// +patchMergeKey=name
 	// +patchStrategy=merge
 	UserDefinedMetrics []UserDefinedMetric `json:"userDefinedMetrics,omitempty" patchStrategy:"merge" patchMergeKey:"name"`
+	// Stats pertaining to swap resources. This is reported to non-windows systems only.
+	// +optional
+	Swap *SwapStats `json:"swap,omitempty"`
 }
 
 // PodReference contains enough information to locate the referenced pod.
@@ -237,6 +246,19 @@ type MemoryStats struct {
 	MajorPageFaults *uint64 `json:"majorPageFaults,omitempty"`
 }
 
+// SwapStats contains data about memory usage
+type SwapStats struct {
+	// The time at which these stats were updated.
+	Time metav1.Time `json:"time"`
+	// Available swap memory for use.  This is defined as the <swap-limit> - <current-swap-usage>.
+	// If swap limit is undefined, this value is omitted.
+	// +optional
+	SwapAvailableBytes *uint64 `json:"swapAvailableBytes,omitempty"`
+	// Total swap memory in use.
+	// +optional
+	SwapUsageBytes *uint64 `json:"swapUsageBytes,omitempty"`
+}
+
 // AcceleratorStats contains stats for accelerators attached to the container.
 type AcceleratorStats struct {
 	// Make of the accelerator (nvidia, amd, google etc.)