diff --git a/src/backend/storage/buffer/freelist.c b/src/backend/storage/buffer/freelist.c
index 3e62448..af7215f 100644
--- a/src/backend/storage/buffer/freelist.c
+++ b/src/backend/storage/buffer/freelist.c
@@ -218,12 +218,21 @@ StrategyGetBuffer(BufferAccessStrategy strategy, bool *lock_held)
 }
 
 /*
- * StrategyFreeBuffer: put a buffer on the freelist
+ * StrategyFreeBuffer: put a buffer on the freelist, unless we're busy
  */
 void
 StrategyFreeBuffer(volatile BufferDesc *buf)
 {
-	LWLockAcquire(BufFreelistLock, LW_EXCLUSIVE);
+	/*
+	 * The buffer is already invalidated and is now an allocation target.
+	 * Adding buffers back onto the freelist is an optimisation only,
+	 * so we can decide to skip this step if the lock is busy.
+	 * This improves the speed of dropping indexes and tables on a busy system.
+	 * If the system is busy the newly invalidated buffers will be reallocated
+	 * within one clock sweep.
+	 */
+	if (!LWLockConditionalAcquire(BufFreelistLock, LW_EXCLUSIVE))
+		return;
 
 	/*
 	 * It is possible that we are told to put something in the freelist that