[#1449] tree: Add ApplyBatch method

Concurrent Apply can lead to child node applies before parent, so
undo/redo operations will perform. This leads to performance degradation
in case of tree with many sublevels.

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

cmd/frostfs-node/config/tree/config.go

@@ -10,6 +10,8 @@ import (
 
 const (
 	subsection = "tree"
+
+	SyncBatchSizeDefault = 1000
 )
 
 // TreeConfig is a wrapper over "tree" config section
@@ -74,6 +76,17 @@ func (c TreeConfig) SyncInterval() time.Duration {
 	return config.DurationSafe(c.cfg, "sync_interval")
 }
 
+// SyncBatchSize returns the value of "sync_batch_size"
+// config parameter from the "tree" section.
+//
+// Returns `SyncBatchSizeDefault` if config value is not specified.
+func (c TreeConfig) SyncBatchSize() int {
+	if v := config.IntSafe(c.cfg, "sync_batch_size"); v > 0 {
+		return int(v)
+	}
+	return SyncBatchSizeDefault
+}
+
 // AuthorizedKeys parses and returns an array of "authorized_keys" config
 // parameter from "tree" section.
 //

cmd/frostfs-node/config/tree/config_test.go

@@ -44,6 +44,7 @@ func TestTreeSection(t *testing.T) {
 		require.Equal(t, 32, treeSec.ReplicationWorkerCount())
 		require.Equal(t, 5*time.Second, treeSec.ReplicationTimeout())
 		require.Equal(t, time.Hour, treeSec.SyncInterval())
+		require.Equal(t, 2000, treeSec.SyncBatchSize())
 		require.Equal(t, expectedKeys, treeSec.AuthorizedKeys())
 	}
 

cmd/frostfs-node/tree.go

@@ -62,6 +62,7 @@ func initTreeService(c *cfg) {
 		tree.WithReplicationTimeout(treeConfig.ReplicationTimeout()),
 		tree.WithReplicationChannelCapacity(treeConfig.ReplicationChannelCapacity()),
 		tree.WithReplicationWorkerCount(treeConfig.ReplicationWorkerCount()),
+		tree.WithSyncBatchSize(treeConfig.SyncBatchSize()),
 		tree.WithAuthorizedKeys(treeConfig.AuthorizedKeys()),
 		tree.WithMetrics(c.metricsCollector.TreeService()),
 		tree.WithAPELocalOverrideStorage(c.cfgObject.cfgAccessPolicyEngine.accessPolicyEngine.LocalStorage()),