From 169887f39f40e6cd0ea5138b263f281056c86c1a Mon Sep 17 00:00:00 2001
From: Roy Crihfield <roy@manteia.ltd>
Date: Mon, 31 Aug 2020 11:03:37 -0500
Subject: [PATCH] number of workers instead of divide depth

update w/ iterator change
---
 cmd/stateSnapshot.go    |  8 ++++----
 pkg/snapshot/service.go | 11 +++++------
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/cmd/stateSnapshot.go b/cmd/stateSnapshot.go
index 1ea4451..b978e58 100644
--- a/cmd/stateSnapshot.go
+++ b/cmd/stateSnapshot.go
@@ -44,8 +44,8 @@ func stateSnapshot() {
 		logWithCommand.Fatal(err)
 	}
 	height := viper.GetInt64("snapshot.blockHeight")
-	divideDepth := viper.GetInt("snapshot.divideDepth")
-	params := snapshot.SnapshotParams{DivideDepth: divideDepth}
+	workers := viper.GetUint("snapshot.workers")
+	params := snapshot.SnapshotParams{Workers: workers}
 	if height < 0 {
 		if err := snapshotService.CreateLatestSnapshot(params); err != nil {
 			logWithCommand.Fatal(err)
@@ -65,10 +65,10 @@ func init() {
 	stateSnapshotCmd.PersistentFlags().String("leveldb-path", "", "path to primary datastore")
 	stateSnapshotCmd.PersistentFlags().String("ancient-path", "", "path to ancient datastore")
 	stateSnapshotCmd.PersistentFlags().String("block-height", "", "blockheight to extract state at")
-	stateSnapshotCmd.PersistentFlags().Int("divide-depth", 0, "trie depth to divide concurrent work at")
+	stateSnapshotCmd.PersistentFlags().Int("workers", 0, "number of concurrent workers to use")
 
 	viper.BindPFlag("leveldb.path", stateSnapshotCmd.PersistentFlags().Lookup("leveldb-path"))
 	viper.BindPFlag("leveldb.ancient", stateSnapshotCmd.PersistentFlags().Lookup("ancient-path"))
 	viper.BindPFlag("snapshot.blockHeight", stateSnapshotCmd.PersistentFlags().Lookup("block-height"))
-	viper.BindPFlag("snapshot.divideDepth", stateSnapshotCmd.PersistentFlags().Lookup("divide-depth"))
+	viper.BindPFlag("snapshot.workers", stateSnapshotCmd.PersistentFlags().Lookup("workers"))
 }
diff --git a/pkg/snapshot/service.go b/pkg/snapshot/service.go
index 8edf7be..af9289d 100644
--- a/pkg/snapshot/service.go
+++ b/pkg/snapshot/service.go
@@ -39,7 +39,6 @@ var (
 	emptyNode, _      = rlp.EncodeToBytes([]byte{})
 	emptyCodeHash     = crypto.Keccak256([]byte{})
 	emptyContractRoot = crypto.Keccak256Hash(emptyNode)
-	spawnDepth		  = 2
 )
 
 type Service struct {
@@ -67,7 +66,7 @@ func NewSnapshotService(con ServiceConfig) (*Service, error) {
 
 type SnapshotParams struct {
 	Height uint64
-	DivideDepth int
+	Workers uint
 }
 
 func (s *Service) CreateSnapshot(params SnapshotParams) error {
@@ -88,8 +87,8 @@ func (s *Service) CreateSnapshot(params SnapshotParams) error {
 	if err != nil {
 		return err
 	}
-	if params.DivideDepth > 0 {
-		return s.createSnapshotAsync(t, headerID, params.DivideDepth)
+	if params.Workers > 0 {
+		return s.createSnapshotAsync(t, headerID, params.Workers)
 	} else {
 		return s.createSnapshot(t.NodeIterator(nil), headerID)
 	}
@@ -200,12 +199,12 @@ func (s *Service) createSnapshot(it iter.NodeIterator, headerID int64) error {
 }
 
 // Full-trie snapshot using goroutines
-func (s *Service) createSnapshotAsync(tree state.Trie, headerID int64, depth int) error {
+func (s *Service) createSnapshotAsync(tree state.Trie, headerID int64, workers uint) error {
 	errors := make(chan error)
 	finished := make(chan bool)
 	var wg sync.WaitGroup
 
-	iter.VisitSubtries(tree, depth, func (it iter.NodeIterator) {
+	iter.VisitSubtries(tree, workers, func (it iter.NodeIterator) {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()