ytdlp

src/export/nfs/kvhandler.go

@@ -9,6 +9,8 @@ import (
 
 	"git.kmsign.ru/royalcat/tstor/pkg/go-nfs"
 	"git.kmsign.ru/royalcat/tstor/src/config"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/metric"
 
 	"github.com/google/uuid"
 	"github.com/royalcat/kv"
@@ -40,6 +42,8 @@ func bytesToPath(path []string) string {
 	return strings.Join(path, sep)
 }
 
+var kvhandlerMeter = otel.Meter("git.kmsign.ru/royalcat/tstor/src/export/nfs.kvhandler")
+
 // NewKvHandler provides a basic to/from-file handle cache that can be tuned with a smaller cache of active directory listings.
 func NewKvHandler(h nfs.Handler, fs nfs.Filesystem) (nfs.Handler, error) {
 	activeHandles, err := kv.NewBadgerKVMarhsler[uuid.UUID, handle](path.Join(config.Config.Mounts.NFS.CachePath, "handlers"))
@@ -54,12 +58,24 @@ func NewKvHandler(h nfs.Handler, fs nfs.Filesystem) (nfs.Handler, error) {
 		return true
 	})
 
-	return &CachingHandler{
+	c := &CachingHandler{
 		Handler:       h,
 		fs:            fs,
 		activeHandles: activeHandles,
 		reverseCache:  reverseCache,
-	}, nil
+	}
+
+	_, err = kvhandlerMeter.Int64ObservableGauge("nfs.activehandles",
+		metric.WithInt64Callback(func(ctx context.Context, io metric.Int64Observer) error {
+			io.Observe(int64(c.ActiveHandlers()))
+			return nil
+		}),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return c, nil
 }
 
 // CachingHandler implements to/from handle via an LRU cache.
@@ -135,11 +151,20 @@ func (c *CachingHandler) InvalidateHandle(fs nfs.Filesystem, handle []byte) erro
 	return c.activeHandles.Delete(ctx, id)
 }
 
-const maxInt = int(^uint(0) >> 1)
+// const maxInt = int(^uint(0) >> 1)
+const maxHandlers = 8129
 
 // HandleLimit exports how many file handles can be safely stored by this cache.
 func (c *CachingHandler) HandleLimit() int {
-	return maxInt
+	return maxHandlers
+}
+
+// HandleLimit exports how many file handles can be safely stored by this cache.
+func (c *CachingHandler) ActiveHandlers() int {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+
+	return len(c.reverseCache)
 }
 
 // func hasPrefix(path, prefix []string) bool {