[#146] native: Add NetworkInfo cache

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

internal/native/cache.go

@@ -0,0 +1,58 @@
+package native
+
+import (
+	"context"
+	"sync"
+	"time"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
+)
+
+const networkCacheTTL = time.Minute
+
+var networkInfoCache = &networkInfoCacheT{}
+
+type networkInfoCacheT struct {
+	guard   sync.RWMutex
+	current *netmap.NetworkInfo
+	fetchTS time.Time
+}
+
+func (c *networkInfoCacheT) getOrFetch(ctx context.Context, cli *client.Client) (*netmap.NetworkInfo, error) {
+	if v := c.get(); v != nil {
+		return v, nil
+	}
+	return c.fetch(ctx, cli)
+}
+
+func (c *networkInfoCacheT) get() *netmap.NetworkInfo {
+	c.guard.RLock()
+	defer c.guard.RUnlock()
+
+	if c.current == nil || time.Since(c.fetchTS) > networkCacheTTL {
+		return nil
+	}
+
+	return c.current
+}
+
+func (c *networkInfoCacheT) fetch(ctx context.Context, cli *client.Client) (*netmap.NetworkInfo, error) {
+	c.guard.Lock()
+	defer c.guard.Unlock()
+
+	if time.Since(c.fetchTS) <= networkCacheTTL {
+		return c.current, nil
+	}
+
+	res, err := cli.NetworkInfo(ctx, client.PrmNetworkInfo{})
+	if err != nil {
+		return nil, err
+	}
+
+	v := res.Info()
+	c.current = &v
+	c.fetchTS = time.Now()
+
+	return c.current, nil
+}

internal/native/client.go

@@ -437,12 +437,12 @@ func put(vu modules.VU, cli *client.Client, prepareLocally bool, tok *session.Ob
 		prm.MaxChunkLength = chunkSize
 	}
 	if prepareLocally {
-		res, err := cli.NetworkInfo(vu.Context(), client.PrmNetworkInfo{})
+		ni, err := networkInfoCache.getOrFetch(vu.Context(), cli)
 		if err != nil {
 			return nil, err
 		}
-		prm.MaxSize = res.Info().MaxObjectSize()
-		prm.EpochSource = epochSource(res.Info().CurrentEpoch())
+		prm.MaxSize = ni.MaxObjectSize()
+		prm.EpochSource = epochSource(ni.CurrentEpoch())
 		prm.WithoutHomomorphHash = true
 		if maxObjSize > 0 {
 			prm.MaxSize = maxObjSize