diff --git a/exec.c b/exec.c
index d9be575..076d26b 100644
--- a/exec.c
+++ b/exec.c
@@ -2412,6 +2412,9 @@ ram_addr_t qemu_ram_alloc(ram_addr_t size)
      new_block = qemu_malloc(sizeof(*new_block));

      new_block->host = qemu_vmalloc(size);
+#ifdef MADV_MERGEABLE
+    madvise(new_block->host, size, MADV_MERGEABLE);
+#endif
      new_block->offset = last_ram_offset;
      new_block->length = size;