runtime: add pod overhead metrics

Add pod overhead metrics for CPU and memory to help with calculating sandbox overhead.

Fixes: #399

Signed-off-by: bin liu <bin@hyper.sh>

docs/design/data/metrics.yaml

@@ -1698,6 +1698,28 @@ components:
               fixed: false
               values: []
           since: 2.0.0
+        - name: kata_shim_pod_overhead_cpu
+          type: GAUGE
+          unit: "percent"
+          help: Kata Pod overhead for CPU resources(percent).
+          labels:
+            - name: sandbox_id
+              desc: ""
+              manually_edit: false
+              fixed: false
+              values: []
+          since: 2.0.0
+        - name: kata_shim_pod_overhead_memory_in_bytes
+          type: GAUGE
+          unit: bytes
+          help: Kata Pod overhead for memory resources(bytes).
+          labels:
+            - name: sandbox_id
+              desc: ""
+              manually_edit: false
+              fixed: false
+              values: []
+          since: 2.0.0
         - name: kata_shim_proc_stat
           type: GAUGE
           unit: ""

docs/design/kata-2-0-metrics.md

@@ -309,6 +309,8 @@ Metrics about Kata containerd shim v2 process.
 | `kata_shim_go_threads`: <br> Number of OS threads created. | `GAUGE` |  | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_io_stat`: <br> Kata containerd shim v2 process IO statistics. | `GAUGE` |  | <ul><li>`item` (see `/proc/<pid>/io`)<ul><li>`cancelledwritebytes`</li><li>`rchar`</li><li>`readbytes`</li><li>`syscr`</li><li>`syscw`</li><li>`wchar`</li><li>`writebytes`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_netdev`: <br> Kata containerd shim v2 network devices statistics. | `GAUGE` |  | <ul><li>`interface` (network device name)</li><li>`item` (see `/proc/net/dev`)<ul><li>`recv_bytes`</li><li>`recv_compressed`</li><li>`recv_drop`</li><li>`recv_errs`</li><li>`recv_fifo`</li><li>`recv_frame`</li><li>`recv_multicast`</li><li>`recv_packets`</li><li>`sent_bytes`</li><li>`sent_carrier`</li><li>`sent_colls`</li><li>`sent_compressed`</li><li>`sent_drop`</li><li>`sent_errs`</li><li>`sent_fifo`</li><li>`sent_packets`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
+| `kata_shim_pod_overhead_cpu`: <br> Kata Pod overhead for CPU resources(percent). | `GAUGE` | percent | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |
+| `kata_shim_pod_overhead_memory_in_bytes`: <br> Kata Pod overhead for memory resources(bytes). | `GAUGE` | `bytes` | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_proc_stat`: <br> Kata containerd shim v2 process statistics. | `GAUGE` |  | <ul><li>`item` (see `/proc/<pid>/stat`)<ul><li>`cstime`</li><li>`cutime`</li><li>`stime`</li><li>`utime`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_proc_status`: <br> Kata containerd shim v2 process status. | `GAUGE` |  | <ul><li>`item` (see `/proc/<pid>/status`)<ul><li>`hugetlbpages`</li><li>`nonvoluntary_ctxt_switches`</li><li>`rssanon`</li><li>`rssfile`</li><li>`rssshmem`</li><li>`vmdata`</li><li>`vmexe`</li><li>`vmhwm`</li><li>`vmlck`</li><li>`vmlib`</li><li>`vmpeak`</li><li>`vmpin`</li><li>`vmpmd`</li><li>`vmpte`</li><li>`vmrss`</li><li>`vmsize`</li><li>`vmstk`</li><li>`vmswap`</li><li>`voluntary_ctxt_switches`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_process_cpu_seconds_total`: <br> Total user and system CPU time spent in seconds. | `COUNTER` | `seconds` | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |