Document Antrea component metrics

Add the list of metrics which are exposed by Antrea agent and controller
in the integration doc for reference.

docs/prometheus-integration.md

@@ -49,21 +49,6 @@ rules:
   verbs: ["get"]
 ```
 
-### Antrea Metrics Listener Access
-To scrape the metrics from Antrea Controller and Agent, Prometheus needs the
-following permissions
-```yaml
-kind: ClusterRole
-apiVersion: rbac.authorization.k8s.io/v1beta1
-metadata:
-  name: prometheus-antrea
-rules:
-- nonResourceURLs:
-  - /metrics
-  verbs:
-  - get
-```
-
 ### Antrea Components Scraping configuration
 Add the following jobs to Prometheus scraping configuration to enable metrics
 collection from Antrea components
@@ -106,3 +91,163 @@ The configuration file above can be used to deploy Prometheus Server with
 scraping configuration for Antrea services.
 To deploy this configuration use
 `kubectl apply -f build/yamls/antrea-prometheus.yml`
+
+# Antrea Prometheus Metrics
+Antrea Controller and Agents expose various metrics, some are provided by the 
+Antrea components and others are provided by 3rd party components which are used
+by the Antrea components.
+
+Below is a list of metrics, provided by the components and by 3rd parties.
+
+## Antrea Controller Metrics
+**antrea_controller_address_group_processed:** The total number of 
+address-group processed  
+**antrea_controller_address_group_sync_duration_milliseconds:** The duration 
+of syncing address-group  
+**antrea_controller_applied_to_group_processed:** The total number of 
+applied-to-group processed  
+**antrea_controller_applied_to_group_sync_duration_milliseconds:** The 
+duration of syncing applied-to-group  
+**antrea_controller_length_address_group_queue:** The length of 
+AddressGroupQueue  
+**antrea_controller_length_applied_to_group_queue:** The length of 
+AppliedToGroupQueue  
+**antrea_controller_length_network_policy_queue:** The length of 
+InternalNetworkPolicyQueue  
+**antrea_controller_network_policy_processed:** The total number of 
+internal-networkpolicy processed  
+**antrea_controller_network_policy_sync_duration_milliseconds:** The duration 
+of syncing internal-networkpolicy  
+**antrea_controller_runtime_info:** Antrea controller runtime info, defined as 
+labels. The value of the gauge is always set to 1.  
+
+## Antrea Agent Metrics
+**antrea_agent_local_pod_count:** Number of pods on local node which are 
+managed by the Antrea Agent.  
+**antrea_agent_ovs_flow_table:** OVS flow table flow count.  
+**antrea_agent_runtime_info:** Antrea agent runtime info , defined as labels. 
+The value of the gauge is always set to 1.  
+
+## Common Metrics Provided by Infrastructure
+### Apiserver Metrics
+**apiserver_audit_event_total:** Counter of audit events generated and sent to 
+the audit backend.  
+**apiserver_audit_requests_rejected_total:** Counter of apiserver requests 
+rejected due to an error in audit logging backend.  
+**apiserver_client_certificate_expiration_seconds:** Distribution of the 
+remaining lifetime on the certificate used to authenticate a request.  
+**apiserver_current_inflight_requests:** Maximal number of currently used 
+inflight request limit of this apiserver per request kind in last second.  
+**apiserver_longrunning_gauge:** Gauge of all active long-running apiserver 
+requests broken out by verb, group, version, resource, scope and component. Not 
+all requests are tracked this way.  
+**apiserver_registered_watchers:** Number of currently registered watchers for 
+a given resources  
+**apiserver_request_count:** (Deprecated) Counter of apiserver requests broken 
+out for each verb, group, version, resource, scope, component, client, and HTTP 
+response contentType and code.  
+**apiserver_request_duration_seconds:** Response latency distribution in 
+seconds for each verb, dry run value, group, version, resource, subresource, 
+scope and component.  
+**apiserver_request_latencies:** (Deprecated) Response latency distribution in 
+microseconds for each verb, group, version, resource, subresource, scope and 
+component.  
+**apiserver_request_latencies_summary:** (Deprecated) Response latency summary 
+in microseconds for each verb, group, version, resource, subresource, scope and 
+component.  
+**apiserver_request_total:** Counter of apiserver requests broken out for each 
+verb, dry run value, group, version, resource, scope, component, client, and 
+HTTP response contentType and code.  
+**apiserver_response_sizes:** Response size distribution in bytes for each 
+group, version, verb, resource, subresource, scope and component.  
+**apiserver_storage_data_key_generation_duration_seconds:** Latencies in 
+seconds of data encryption key(DEK) generation operations.  
+**apiserver_storage_data_key_generation_failures_total:** Total number of 
+failed data encryption key(DEK) generation operations.  
+**apiserver_storage_data_key_generation_latencies_microseconds:** (Deprecated) 
+Latencies in microseconds of data encryption key(DEK) generation operations.  
+**apiserver_storage_envelope_transformation_cache_misses_total:** Total number 
+of cache misses while accessing key decryption key(KEK).  
+### Authenticated Metrics
+**authenticated_user_requests:** Counter of authenticated requests broken out 
+by username.  
+### Etcd Metrics
+**etcd_helper_cache_entry_count:** (Deprecated) Counter of etcd helper cache 
+entries. This can be different from etcd_helper_cache_miss_count because two 
+concurrent threads can miss the cache and generate the same entry twice.  
+**etcd_helper_cache_entry_total:** Counter of etcd helper cache entries. This 
+can be different from etcd_helper_cache_miss_count because two concurrent 
+threads can miss the cache and generate the same entry twice.  
+**etcd_helper_cache_hit_count:** (Deprecated) Counter of etcd helper cache 
+hits.   
+**etcd_helper_cache_hit_total:** Counter of etcd helper cache hits.  
+**etcd_helper_cache_miss_count:** (Deprecated) Counter of etcd helper cache 
+miss.  
+**etcd_helper_cache_miss_total:** Counter of etcd helper cache miss.  
+**etcd_request_cache_add_duration_seconds:** Latency in seconds of adding an 
+object to etcd cache  
+**etcd_request_cache_add_latencies_summary:** (Deprecated) Latency in 
+microseconds of adding an object to etcd cache  
+**etcd_request_cache_get_duration_seconds:** Latency in seconds of getting an 
+object from etcd cache  
+**etcd_request_cache_get_latencies_summary:** (Deprecated) Latency in 
+microseconds of getting an object from etcd cache 
+### Go Metrics
+**go_gc_duration_seconds:** A summary of the GC invocation durations.  
+**go_goroutines:** Number of goroutines that currently exist.  
+**go_info:** Information about the Go environment.  
+**go_memstats_alloc_bytes:** Number of bytes allocated and still in use.  
+**go_memstats_alloc_bytes_total:** Total number of bytes allocated, even if 
+freed.  
+**go_memstats_buck_hash_sys_bytes:** Number of bytes used by the profiling 
+bucket hash table.  
+**go_memstats_frees_total:** Total number of frees.  
+**go_memstats_gc_cpu_fraction:** The fraction of this program's available CPU 
+time used by the GC since the program started.  
+**go_memstats_gc_sys_bytes:** Number of bytes used for garbage collection 
+system metadata.  
+**go_memstats_heap_alloc_bytes:** Number of heap bytes allocated and still in 
+use.  
+**go_memstats_heap_idle_bytes:** Number of heap bytes waiting to be used.  
+**go_memstats_heap_inuse_bytes:** Number of heap bytes that are in use.  
+**go_memstats_heap_objects:** Number of allocated objects.  
+**go_memstats_heap_released_bytes:** Number of heap bytes released to OS.  
+**go_memstats_heap_sys_bytes:** Number of heap bytes obtained from system.  
+**go_memstats_last_gc_time_seconds:** Number of seconds since 1970 of last 
+garbage collection.  
+**go_memstats_lookups_total:** Total number of pointer lookups.  
+**go_memstats_mallocs_total:** Total number of mallocs.  
+**go_memstats_mcache_inuse_bytes:** Number of bytes in use by mcache 
+structures.  
+**go_memstats_mcache_sys_bytes:** Number of bytes used for mcache structures 
+obtained from system.  
+**go_memstats_mspan_inuse_bytes:** Number of bytes in use by mspan structures.  
+**go_memstats_mspan_sys_bytes:** Number of bytes used for mspan structures 
+obtained from system.  
+**go_memstats_next_gc_bytes:** Number of heap bytes when next garbage 
+collection will take place.  
+**go_memstats_other_sys_bytes:** Number of bytes used for other system 
+allocations.  
+**go_memstats_stack_inuse_bytes:** Number of bytes in use by the stack 
+allocator.  
+**go_memstats_stack_sys_bytes:** Number of bytes obtained from system for 
+stack allocator.  
+**go_memstats_sys_bytes:** Number of bytes obtained from system.  
+**go_threads:** Number of OS threads created.  
+### HTTP Metrics
+**http_request_duration_microseconds:** The HTTP request latencies in 
+microseconds.  
+**http_request_size_bytes:** The HTTP request sizes in bytes.  
+**http_requests_total:** Total number of HTTP requests made.  
+**http_response_size_bytes:** The HTTP response sizes in bytes.  
+### Process Metrics
+**process_cpu_seconds_total:** Total user and system CPU time spent in 
+seconds.  
+**process_max_fds:** Maximum number of open file descriptors.  
+**process_open_fds:** Number of open file descriptors.  
+**process_resident_memory_bytes:** Resident memory size in bytes.  
+**process_start_time_seconds:** Start time of the process since unix epoch in 
+seconds.  
+**process_virtual_memory_bytes:** Virtual memory size in bytes.  
+**process_virtual_memory_max_bytes:** Maximum amount of virtual memory 
+available in bytes.