1 files changed, 13 insertions, 1 deletions

diff --git a/src/main.cpp b/src/main.cpp
index 5d0b70a..37a15c6 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -4226,7 +4226,19 @@ bool BitcoinMiner(int nThreadId)
             vector<char> vfAlreadyAdded(mapTransactions.size());
             bool fFoundSomething = true;
             unsigned int nBlockSize = 0;
-            while (fFoundSomething && nBlockSize < MAX_SIZE/2)
+            // Assembly must stop below the consensus cap that CheckBlock()
+            // enforces, or we mine a block our own node then rejects.
+            //
+            // This used to read MAX_SIZE/2 (16 MB), which was consistent while
+            // CheckBlock() also tested against MAX_SIZE (32 MB). Adding
+            // MAX_BLOCK_SIZE inverted it: assembly could fill 16 MB and
+            // validation would refuse anything over 1 MB, so a full mempool
+            // meant solving a block and throwing it away -- with this pool at
+            // ~90% of hashrate, that is the network stalling, not just us.
+            //
+            // Half the cap, keeping the original margin: the test runs before
+            // a transaction is added, so the loop can overshoot by one tx.
+            while (fFoundSomething && nBlockSize < MAX_BLOCK_SIZE/2)
             {
                 fFoundSomething = false;
                 unsigned int n = 0;