chore: add async search limits metrics

asyncsearcher/async_searcher.go

@@ -17,8 +17,6 @@ import (
 	"time"
 
 	"github.com/google/uuid"
-	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promauto"
 	"go.uber.org/zap"
 
 	"github.com/ozontech/seq-db/bytespool"
@@ -49,33 +47,6 @@ const (
 	infoVersion2                        // MIDs stored in nanoseconds
 )
 
-var (
-	asyncSearchActiveSearches = promauto.NewGauge(prometheus.GaugeOpts{
-		Namespace: "seq_db_store",
-		Subsystem: "async_search",
-		Name:      "in_progress",
-		Help:      "Number of active async searches in progress",
-	})
-	asyncSearchDiskUsage = promauto.NewGaugeVec(prometheus.GaugeOpts{
-		Namespace: "seq_db_store",
-		Subsystem: "async_search",
-		Name:      "disk_usage_bytes",
-		Help:      "Disk space used by async search files in bytes by file type",
-	}, []string{"file_type"})
-	asyncSearchStoredRequests = promauto.NewGauge(prometheus.GaugeOpts{
-		Namespace: "seq_db_store",
-		Subsystem: "async_search",
-		Name:      "stored_requests",
-		Help:      "Number of stored async search requests",
-	})
-	asyncSearchReadOnly = promauto.NewGauge(prometheus.GaugeOpts{
-		Namespace: "seq_db_store",
-		Subsystem: "async_search",
-		Name:      "read_only",
-		Help:      "Indicates if store is in async search read-only mode (can not start a new async search) due to disk usage limits",
-	})
-)
-
 type MappingProvider interface {
 	GetMapping() seq.Mapping
 }
@@ -134,6 +105,10 @@ func MustStartAsync(config AsyncSearcherConfig, mp MappingProvider, fracs fracma
 		go as.processRequest(id, fracs)
 	}
 
+	// set limit metrics that allow us to calculate alerts' thresholds
+	asyncSearchDiskUsageLimit.Set(float64(config.MaxSize))
+	asyncSearchConcurrencyLimit.Set(float64(config.Workers))
+
 	go as.startMaintenance()
 
 	return as

asyncsearcher/metrics.go

@@ -0,0 +1,45 @@
+package asyncsearcher
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	asyncSearchActiveSearches = promauto.NewGauge(prometheus.GaugeOpts{
+		Namespace: "seq_db_store",
+		Subsystem: "async_search",
+		Name:      "in_progress",
+		Help:      "Number of active async searches in progress",
+	})
+	asyncSearchConcurrencyLimit = promauto.NewGauge(prometheus.GaugeOpts{
+		Namespace: "seq_db_store",
+		Subsystem: "async_search",
+		Name:      "concurrency_limit",
+		Help:      "Maximum number of simultaneously running async searches",
+	})
+	asyncSearchDiskUsage = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: "seq_db_store",
+		Subsystem: "async_search",
+		Name:      "disk_usage_bytes",
+		Help:      "Disk space used by async search files in bytes by file type",
+	}, []string{"file_type"})
+	asyncSearchDiskUsageLimit = promauto.NewGauge(prometheus.GaugeOpts{
+		Namespace: "seq_db_store",
+		Subsystem: "async_search",
+		Name:      "disk_usage_limit_bytes",
+		Help:      "Maximum disk space async searches is allowed to use in bytes",
+	})
+	asyncSearchStoredRequests = promauto.NewGauge(prometheus.GaugeOpts{
+		Namespace: "seq_db_store",
+		Subsystem: "async_search",
+		Name:      "stored_requests",
+		Help:      "Number of stored async search requests",
+	})
+	asyncSearchReadOnly = promauto.NewGauge(prometheus.GaugeOpts{
+		Namespace: "seq_db_store",
+		Subsystem: "async_search",
+		Name:      "read_only",
+		Help:      "Indicates if store is in async search read-only mode (can not start a new async search) due to disk usage limits",
+	})
+)