Mempool Update Cut-Through Optimization

Often when we're updating mempool entries we update entries that we
ultimately end up removing the updated entries shortly thereafter. This
patch makes it so that we filter for such entries a bit earlier in
processing, which yields a mild improvement for these cases, and is
negligible overhead otherwise.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index 7efd176e00..f40941ad08 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -348,7 +348,9 @@ void CChainState::MaybeUpdateMempoolForReorg(
     // previously-confirmed transactions back to the mempool.
     // UpdateTransactionsFromBlock finds descendants of any transactions in
     // the disconnectpool that were added back and cleans up the mempool state.
-    m_mempool->UpdateTransactionsFromBlock(vHashUpdate);
+    const uint64_t ancestor_count_limit = gArgs.GetIntArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT);
+    const uint64_t ancestor_size_limit = gArgs.GetIntArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT) * 1000;
+    m_mempool->UpdateTransactionsFromBlock(vHashUpdate, ancestor_size_limit, ancestor_count_limit);
 
     const auto check_final_and_mature = [this, flags=STANDARD_LOCKTIME_VERIFY_FLAGS](CTxMemPool::txiter it)
         EXCLUSIVE_LOCKS_REQUIRED(m_mempool->cs, ::cs_main) {