From d35efe1efc0dbeae0667baade2a40be08511c13e Mon Sep 17 00:00:00 2001
From: Martin Zumsande <mzumsande@gmail.com>
Date: Mon, 10 Jun 2024 18:20:15 -0400
Subject: [PATCH] p2p: Start downloading historical blocks from common ancestor
Otherwise, if the background tip is not an ancestor of the snapshot, blocks in between that ancestor up to the height of the background tip will never be requested.
Co-authored-by: Martin Zumsande <mzumsande@gmail.com>
Co-authored-by: Alfonso Roman Zubeldia <19962151+alfonsoromanz@users.noreply.github.com>
---
src/net_processing.cpp | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 6374cb52c18..babff0796f3 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -6293,10 +6293,13 @@ bool PeerManagerImpl::SendMessages(CNode* pto)
// before the background chainstate to prioritize getting to network tip.
FindNextBlocksToDownload(*peer, get_inflight_budget(), vToDownload, staller);
if (m_chainman.BackgroundSyncInProgress() && !IsLimitedPeer(*peer)) {
+ // If the background tip is not an ancestor of the snapshot block,
+ // we need to start requesting blocks from their last common ancestor.
+ const CBlockIndex *from_tip = LastCommonAncestor(m_chainman.GetBackgroundSyncTip(), m_chainman.GetSnapshotBaseBlock());
TryDownloadingHistoricalBlocks(
*peer,
get_inflight_budget(),
- vToDownload, m_chainman.GetBackgroundSyncTip(),
+ vToDownload, from_tip,
Assert(m_chainman.GetSnapshotBaseBlock()));
}
for (const CBlockIndex *pindex : vToDownload) {