From b71f771acbfcdbaa273a15e126051b79a51fc542 Mon Sep 17 00:00:00 2001
From: whyrusleeping <why@ipfs.io>
Date: Mon, 22 Jun 2020 16:09:05 -0700
Subject: [PATCH 1/2] run block validation for tipsets in parallel

---
 chain/sync.go | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/chain/sync.go b/chain/sync.go
index 26f30d95b..19ddac108 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -466,16 +466,25 @@ func (syncer *Syncer) ValidateTipSet(ctx context.Context, fts *store.FullTipSet)
 		return nil
 	}
 
+	var futures []async.ErrorFuture
 	for _, b := range fts.Blocks {
-		if err := syncer.ValidateBlock(ctx, b); err != nil {
-			if isPermanent(err) {
-				syncer.bad.Add(b.Cid(), err.Error())
+		futures = append(futures, async.Err(func() error {
+			if err := syncer.ValidateBlock(ctx, b); err != nil {
+				if isPermanent(err) {
+					syncer.bad.Add(b.Cid(), err.Error())
+				}
+				return xerrors.Errorf("validating block %s: %w", b.Cid(), err)
 			}
-			return xerrors.Errorf("validating block %s: %w", b.Cid(), err)
-		}
 
-		if err := syncer.sm.ChainStore().AddToTipSetTracker(b.Header); err != nil {
-			return xerrors.Errorf("failed to add validated header to tipset tracker: %w", err)
+			if err := syncer.sm.ChainStore().AddToTipSetTracker(b.Header); err != nil {
+				return xerrors.Errorf("failed to add validated header to tipset tracker: %w", err)
+			}
+			return nil
+		}))
+	}
+	for _, f := range futures {
+		if err := f.AwaitContext(ctx); err != nil {
+			return err
 		}
 	}
 	return nil

From 9e70e9524231ae98375a2ac93b3be4bd22e78992 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Magiera?= <magik6k@gmail.com>
Date: Tue, 23 Jun 2020 13:21:01 +0200
Subject: [PATCH 2/2] sync: Correctly pass blocks to ValidateBlock

---
 chain/sync.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/chain/sync.go b/chain/sync.go
index 19ddac108..f20637c9e 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -468,6 +468,8 @@ func (syncer *Syncer) ValidateTipSet(ctx context.Context, fts *store.FullTipSet)
 
 	var futures []async.ErrorFuture
 	for _, b := range fts.Blocks {
+		b := b // rebind to a scoped variable
+
 		futures = append(futures, async.Err(func() error {
 			if err := syncer.ValidateBlock(ctx, b); err != nil {
 				if isPermanent(err) {