1 files changed, 29 insertions, 21 deletions

diff --git a/src/qt/clientmodel.cpp b/src/qt/clientmodel.cpp
index e8146982f9..159b0d3df3 100644
--- a/src/qt/clientmodel.cpp
+++ b/src/qt/clientmodel.cpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2011-2019 The Bitcoin Core developers
+// Copyright (c) 2011-2020 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -15,6 +15,7 @@
 #include <net.h>
 #include <netbase.h>
 #include <util/system.h>
+#include <validation.h>
 
 #include <stdint.h>
 
@@ -105,6 +106,14 @@ int64_t ClientModel::getHeaderTipTime() const
     return cachedBestHeaderTime;
 }
 
+int ClientModel::getNumBlocks() const
+{
+    if (m_cached_num_blocks == -1) {
+        m_cached_num_blocks = m_node.getNumBlocks();
+    }
+    return m_cached_num_blocks;
+}
+
 void ClientModel::updateNumConnections(int numConnections)
 {
     Q_EMIT numConnectionsChanged(numConnections);
@@ -226,33 +235,32 @@ static void BannedListChanged(ClientModel *clientmodel)
     assert(invoked);
 }
 
-static void BlockTipChanged(ClientModel *clientmodel, bool initialSync, int height, int64_t blockTime, double verificationProgress, bool fHeader)
+static void BlockTipChanged(ClientModel* clientmodel, SynchronizationState sync_state, int height, int64_t blockTime, double verificationProgress, bool fHeader)
 {
-    // lock free async UI updates in case we have a new block tip
-    // during initial sync, only update the UI if the last update
-    // was > 250ms (MODEL_UPDATE_DELAY) ago
-    int64_t now = 0;
-    if (initialSync)
-        now = GetTimeMillis();
-
-    int64_t& nLastUpdateNotification = fHeader ? nLastHeaderTipUpdateNotification : nLastBlockTipUpdateNotification;
-
     if (fHeader) {
         // cache best headers time and height to reduce future cs_main locks
         clientmodel->cachedBestHeaderHeight = height;
         clientmodel->cachedBestHeaderTime = blockTime;
+    } else {
+        clientmodel->m_cached_num_blocks = height;
     }
-    // if we are in-sync or if we notify a header update, update the UI regardless of last update time
-    if (fHeader || !initialSync || now - nLastUpdateNotification > MODEL_UPDATE_DELAY) {
-        //pass an async signal to the UI thread
-        bool invoked = QMetaObject::invokeMethod(clientmodel, "numBlocksChanged", Qt::QueuedConnection,
-                                  Q_ARG(int, height),
-                                  Q_ARG(QDateTime, QDateTime::fromTime_t(blockTime)),
-                                  Q_ARG(double, verificationProgress),
-                                  Q_ARG(bool, fHeader));
-        assert(invoked);
-        nLastUpdateNotification = now;
+
+    // Throttle GUI notifications about (a) blocks during initial sync, and (b) both blocks and headers during reindex.
+    const bool throttle = (sync_state != SynchronizationState::POST_INIT && !fHeader) || sync_state == SynchronizationState::INIT_REINDEX;
+    const int64_t now = throttle ? GetTimeMillis() : 0;
+    int64_t& nLastUpdateNotification = fHeader ? nLastHeaderTipUpdateNotification : nLastBlockTipUpdateNotification;
+    if (throttle && now < nLastUpdateNotification + MODEL_UPDATE_DELAY) {
+        return;
     }
+
+    bool invoked = QMetaObject::invokeMethod(clientmodel, "numBlocksChanged", Qt::QueuedConnection,
+        Q_ARG(int, height),
+        Q_ARG(QDateTime, QDateTime::fromTime_t(blockTime)),
+        Q_ARG(double, verificationProgress),
+        Q_ARG(bool, fHeader),
+        Q_ARG(SynchronizationState, sync_state));
+    assert(invoked);
+    nLastUpdateNotification = now;
 }
 
 void ClientModel::subscribeToCoreSignals()