[receiver/apache] Add metrics for worker limit, request rate, and traffic throughput

.chloggen/47061-apache-new-metrics.yaml

@@ -0,0 +1,31 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'enhancement'
+
+# The name of the component, or a single word describing the area of concern, (e.g. receiver/filelog)
+component: receiver/apache
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add metrics for max workers, bytes per second, and requests per second.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [47061]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: |
+  Added three new metrics to the Apache receiver:
+  - `apache.worker.limit`: The maximum number of worker slots, derived from the scoreboard length.
+  - `apache.request_rate.io.transmitted`: Average bytes served per second, from the `BytesPerSec` field.
+  - `apache.request_rate.count`: Average requests served per second, from the `ReqPerSec` field.
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

receiver/apachereceiver/documentation.md

@@ -89,6 +89,22 @@ Total time spent on handling requests.
 | ---- | ----------- | ---------- | ----------------------- | --------- | --------- |
 | ms | Sum | Int | Cumulative | true | Development |
 
+### apache.request_rate.count
+
+The average number of requests served per second since the server was started.
+
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| {requests}/s | Gauge | Double | Development |
+
+### apache.request_rate.io.transmitted
+
+The average number of bytes served per second since the server was started.
+
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| By/s | Gauge | Double | Development |
+
 ### apache.requests
 
 The number of requests serviced by the HTTP server per second.
@@ -129,6 +145,14 @@ The amount of time that the server has been running in seconds.
 | ---- | ----------- | ---------- | ----------------------- | --------- | --------- |
 | s | Sum | Int | Cumulative | true | Development |
 
+### apache.worker.limit
+
+The maximum number of worker slots available on the server, derived from the length of the scoreboard.
+
+| Unit | Metric Type | Value Type | Stability |
+| ---- | ----------- | ---------- | --------- |
+| {workers} | Gauge | Int | Development |
+
 ### apache.workers
 
 The number of workers currently attached to the HTTP server.

receiver/apachereceiver/internal/metadata/config.schema.yaml

@@ -94,6 +94,20 @@ $defs:
           enabled:
             type: boolean
             default: true
+      apache.request_rate.count:
+        description: "ApacheRequestRateCountMetricConfig provides config for the apache.request_rate.count metric."
+        type: object
+        properties:
+          enabled:
+            type: boolean
+            default: true
+      apache.request_rate.io.transmitted:
+        description: "ApacheRequestRateIoTransmittedMetricConfig provides config for the apache.request_rate.io.transmitted metric."
+        type: object
+        properties:
+          enabled:
+            type: boolean
+            default: true
       apache.requests:
         description: "ApacheRequestsMetricConfig provides config for the apache.requests metric."
         type: object
@@ -138,6 +152,13 @@ $defs:
           enabled:
             type: boolean
             default: true
+      apache.worker.limit:
+        description: "ApacheWorkerLimitMetricConfig provides config for the apache.worker.limit metric."
+        type: object
+        properties:
+          enabled:
+            type: boolean
+            default: true
       apache.workers:
         description: "ApacheWorkersMetricConfig provides config for the apache.workers metric."
         type: object