From 9981ce7adbadc988adf1a964c97f1555f4f1ddb2 Mon Sep 17 00:00:00 2001
From: Svarog <feanorr@gmail.com>
Date: Wed, 7 Aug 2019 11:30:32 +0300
Subject: [PATCH] [NOD-255] When adding orphans during netsync process - report
 only to debug log, unless number of orphans > k*2 (#357)

* [NOD-255] When orphan blocks arrive from netsync - don't write log unless we are in Debug

* [NOD-255] If there are more than K*2 orphans in pool - report as a potential problem anyway

* [NOD-255] Update comment to explain the K*2 figure
---
 blockdag/process.go | 17 ++++++++++++++++-
 netsync/manager.go  |  3 +++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/blockdag/process.go b/blockdag/process.go
index 514e8cdf1..9ae456bf8 100644
--- a/blockdag/process.go
+++ b/blockdag/process.go
@@ -37,6 +37,10 @@ const (
 	// in the future, just finished the delay
 	BFAfterDelay
 
+	// BFIsSync may be set to indicate that the block was sent as part of the
+	// netsync process
+	BFIsSync
+
 	// BFNone is a convenience value to specifically indicate no flags.
 	BFNone BehaviorFlags = 0
 )
@@ -189,7 +193,18 @@ func (dag *BlockDAG) ProcessBlock(block *util.Block, flags BehaviorFlags) (isOrp
 	}
 
 	if !allParentsExist {
-		log.Infof("Adding orphan block %s", blockHash)
+		// Some orphans during netsync are a normal part of the process, since the anticone
+		// of the chain-split is never explicitly requested.
+		// Therefore, if we are during netsync - don't report orphans to default logs.
+		//
+		// The number K*2 was chosen since in peace times anticone is limited to K blocks,
+		// while some red block can make it a bit bigger, but much more than that indicates
+		// there might be some problem with the netsync process.
+		if flags&BFIsSync == BFIsSync && uint32(len(dag.orphans)) < dag.dagParams.K*2 {
+			log.Debugf("Adding orphan block %s. This is normal part of netsync process", blockHash)
+		} else {
+			log.Infof("Adding orphan block %s", blockHash)
+		}
 		dag.addOrphanBlock(block)
 
 		return true, 0, nil
diff --git a/netsync/manager.go b/netsync/manager.go
index 940e21ad8..e4554585c 100644
--- a/netsync/manager.go
+++ b/netsync/manager.go
@@ -552,6 +552,9 @@ func (sm *SyncManager) handleBlockMsg(bmsg *blockMsg) {
 	if bmsg.isDelayedBlock {
 		behaviorFlags |= blockdag.BFAfterDelay
 	}
+	if bmsg.peer == sm.syncPeer {
+		behaviorFlags |= blockdag.BFIsSync
+	}
 
 	// Process the block to include validation, orphan handling, etc.
 	isOrphan, delay, err := sm.dag.ProcessBlock(bmsg.block, behaviorFlags)