[receiver/sqlserver] Enable sqlserver.page.life_expectance metric

Author: crobert-1

.chloggen/sqlserver_page_life_expectancy.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. filelogreceiver)
+component: receiver/sqlserver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Enable `sqlserver.page.life_expectancy` metric for all configurations
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: []
+
+# (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: |
+  This metric was originally only available when running on Windows, but is
+  now available for all configuration options, including direct connection.
+  Since this metric is enabled by default, users who have direct connection
+  configured will now have this metric emitted by default.
+
+# 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: []

receiver/sqlserverreceiver/documentation.md

@@ -86,8 +86,6 @@ This metric is only available when running on Windows.
 
 Time a page will stay in the buffer pool.
 
-This metric is only available when running on Windows.
-
 | Unit | Metric Type | Value Type |
 | ---- | ----------- | ---------- |
 | s | Gauge | Int |

receiver/sqlserverreceiver/metadata.yaml

@@ -122,7 +122,6 @@ metrics:
     unit: s
     gauge:
       value_type: int
-    extended_documentation: This metric is only available when running on Windows.
   sqlserver.page.split.rate:
     enabled: true
     description: Number of pages split as a result of overflowing index pages.

receiver/sqlserverreceiver/scraper.go

@@ -224,6 +224,7 @@ func (s *sqlServerScraperHelper) recordDatabasePerfCounterMetrics(ctx context.Co
 	const numberOfDeadlocksPerSec = "Number of Deadlocks/sec"
 	const mirrorWritesTransactionPerSec = "Mirrored Write Transactions/sec"
 	const memoryGrantsPending = "Memory Grants Pending"
+	const pageLifeExpectancy = "Page life expectancy"
 	const pageLookupsPerSec = "Page lookups/sec"
 	const processesBlocked = "Processes blocked"
 	const sqlCompilationRate = "SQL Compilations/sec"
@@ -400,6 +401,14 @@ func (s *sqlServerScraperHelper) recordDatabasePerfCounterMetrics(ctx context.Co
 			} else {
 				s.mb.RecordSqlserverDeadlockRateDataPoint(now, val.(float64))
 			}
+		case pageLifeExpectancy:
+			val, err := retrieveInt(row, valueKey)
+			if err != nil {
+				err = fmt.Errorf("failed to parse valueKey for row %d: %w in %s", i, err, pageLifeExpectancy)
+				errs = append(errs, err)
+			} else {
+				s.mb.RecordSqlserverPageLifeExpectancyDataPoint(now, val.(int64))
+			}
 		case pageLookupsPerSec:
 			val, err := retrieveFloat(row, valueKey)
 			if err != nil {