diff --git a/src/validation.cpp b/src/validation.cpp
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -3076,6 +3076,7 @@
 
     CBlockIndex *to_mark_failed = pindex;
     bool pindex_was_in_chain = false;
+    int disconnected = 0;
 
     // Disconnect (descendants of) pindex, and mark them invalid.
     while (true) {
@@ -3097,8 +3098,12 @@
         bool ret = DisconnectTip(config, state, &disconnectpool);
         // DisconnectTip will add transactions to disconnectpool.
         // Adjust the mempool to be consistent with the new tip, adding
-        // transactions back to the mempool if disconnecting was successful.
-        disconnectpool.updateMempoolForReorg(config, /* fAddToMempool = */ ret);
+        // transactions back to the mempool if disconnecting was successful,
+        // and we're not doing a very deep invalidation (in which case
+        // keeping the mempool up to date is probably futile anyway).
+        disconnectpool.updateMempoolForReorg(
+            config, /* fAddToMempool = */ (++disconnected <= 10) && ret);
+
         if (!ret) return false;
         assert(invalid_walk_tip->pprev == chainActive.Tip());