pkg/sql: rename metric tracking SQL activity update job failures

The metric used to track failures of the SQL Activity update job
didn't have a descriptive name, and the help text was grammatically
incorrect. Furthermore, the metric name is the same as a metric used
within the job system, meaning one of these metrics is probably
clobbering the other when writing to TSDB or outputting to
`/_status/vars`.

This patch simply updates the metric name to better describe what it
measures, and fixes the help text description.

Release note (ops change): A new counter metric,
`sql.stats.activity.updates.failed`, has been introduced to measure the
number of update attempts made by the SQL activity updater job that failed with
errors. The SQL activity update job is used to pre-aggregate top K
information within the SQL stats subsystem and write the results to
`system.statement_activity` and `system.transaction_activity`.

docs/generated/metrics/metrics.html

@@ -1079,7 +1079,7 @@
 <tr><td>APPLICATION</td><td>jobs.key_visualizer.resume_completed</td><td>Number of key_visualizer jobs which successfully resumed to completion</td><td>jobs</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
 <tr><td>APPLICATION</td><td>jobs.key_visualizer.resume_failed</td><td>Number of key_visualizer jobs which failed with a non-retriable error</td><td>jobs</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
 <tr><td>APPLICATION</td><td>jobs.key_visualizer.resume_retry_error</td><td>Number of key_visualizer jobs which failed with a retriable error</td><td>jobs</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
-<tr><td>APPLICATION</td><td>jobs.metrics.task_failed</td><td>Number of metrics sql activity updater tasks that failed</td><td>errors</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
+<tr><td>APPLICATION</td><td>jobs.metrics.task_failed</td><td>Number of metrics poller tasks that failed</td><td>errors</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
 <tr><td>APPLICATION</td><td>jobs.migration.currently_idle</td><td>Number of migration jobs currently considered Idle and can be freely shut down</td><td>jobs</td><td>GAUGE</td><td>COUNT</td><td>AVG</td><td>NONE</td></tr>
 <tr><td>APPLICATION</td><td>jobs.migration.currently_paused</td><td>Number of migration jobs currently considered Paused</td><td>jobs</td><td>GAUGE</td><td>COUNT</td><td>AVG</td><td>NONE</td></tr>
 <tr><td>APPLICATION</td><td>jobs.migration.currently_running</td><td>Number of migration jobs currently running in Resume or OnFailOrCancel state</td><td>jobs</td><td>GAUGE</td><td>COUNT</td><td>AVG</td><td>NONE</td></tr>
@@ -1444,6 +1444,7 @@
 <tr><td>APPLICATION</td><td>sql.statements.active</td><td>Number of currently active user SQL statements</td><td>Active Statements</td><td>GAUGE</td><td>COUNT</td><td>AVG</td><td>NONE</td></tr>
 <tr><td>APPLICATION</td><td>sql.statements.active.internal</td><td>Number of currently active user SQL statements (internal queries)</td><td>SQL Internal Statements</td><td>GAUGE</td><td>COUNT</td><td>AVG</td><td>NONE</td></tr>
 <tr><td>APPLICATION</td><td>sql.stats.activity.update.latency</td><td>The latency of updates made by the SQL activity updater job. Includes failed update attempts</td><td>Nanoseconds</td><td>HISTOGRAM</td><td>NANOSECONDS</td><td>AVG</td><td>NONE</td></tr>
+<tr><td>APPLICATION</td><td>sql.stats.activity.updates.failed</td><td>Number of update attempts made by the SQL activity updater job that failed with errors</td><td>failed updatesgi</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
 <tr><td>APPLICATION</td><td>sql.stats.activity.updates.successful</td><td>Number of successful updates made by the SQL activity updater job</td><td>successful updates</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
 <tr><td>APPLICATION</td><td>sql.stats.cleanup.rows_removed</td><td>Number of stale statistics rows that are removed</td><td>SQL Stats Cleanup</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>
 <tr><td>APPLICATION</td><td>sql.stats.discarded.current</td><td>Number of fingerprint statistics being discarded</td><td>Discarded SQL Stats</td><td>COUNTER</td><td>COUNT</td><td>AVG</td><td>NON_NEGATIVE_DERIVATIVE</td></tr>

pkg/sql/sql_activity_update_job.go

@@ -108,7 +108,7 @@ func (j *sqlActivityUpdateJob) Resume(ctx context.Context, execCtxI interface{})
 				updater := newSqlActivityUpdater(settings, execCtx.ExecCfg().InternalDB, nil)
 				if err := updater.TransferStatsToActivity(ctx); err != nil {
 					log.Warningf(ctx, "error running sql activity updater job: %v", err)
-					metrics.NumErrors.Inc(1)
+					metrics.NumFailedUpdates.Inc(1)
 				} else {
 					metrics.NumSuccessfulUpdates.Inc(1)
 				}
@@ -125,7 +125,7 @@ func (j *sqlActivityUpdateJob) Resume(ctx context.Context, execCtxI interface{})
 // ActivityUpdaterMetrics must be public for metrics to get
 // registered
 type ActivityUpdaterMetrics struct {
-	NumErrors            *metric.Counter
+	NumFailedUpdates     *metric.Counter
 	NumSuccessfulUpdates *metric.Counter
 	UpdateLatency        metric.IHistogram
 }
@@ -134,10 +134,10 @@ func (m ActivityUpdaterMetrics) MetricStruct() {}
 
 func newActivityUpdaterMetrics() metric.Struct {
 	return ActivityUpdaterMetrics{
-		NumErrors: metric.NewCounter(metric.Metadata{
-			Name:        "jobs.metrics.task_failed",
-			Help:        "Number of metrics sql activity updater tasks that failed",
-			Measurement: "errors",
+		NumFailedUpdates: metric.NewCounter(metric.Metadata{
+			Name:        "sql.stats.activity.updates.failed",
+			Help:        "Number of update attempts made by the SQL activity updater job that failed with errors",
+			Measurement: "failed updatesgi",
 			Unit:        metric.Unit_COUNT,
 			MetricType:  io_prometheus_client.MetricType_COUNTER,
 		}),