diff --git libmariadb/ma_alloc.c libmariadb/ma_alloc.c
index d6db279e..4526fef0 100644
--- libmariadb/ma_alloc.c
+++ libmariadb/ma_alloc.c
@@ -86,7 +86,7 @@ void * ma_alloc_root(MA_MEM_ROOT *mem_root, size_t Size)
   if (! next)
   {						/* Time to alloc new block */
     get_size= MAX(Size+ALIGN_SIZE(sizeof(MA_USED_MEM)),
-              (mem_root->block_size & ~1) * (mem_root->block_num >> 2));
+              (mem_root->block_size & ~1) * ((mem_root->block_num >> 2) < 4 ? 4 : (mem_root->block_num >> 2)));
 
     if (!(next = (MA_USED_MEM*) malloc(get_size)))
     {