diff --git a/src/stdplus/io_uring.cpp b/src/stdplus/io_uring.cpp
index 7acf2c7..63b9798 100644
--- a/src/stdplus/io_uring.cpp
+++ b/src/stdplus/io_uring.cpp
@@ -65,8 +65,7 @@
     }
 
     io_uring_unregister_files(&ring);
-    files.reserve(files.size() + 1);
-    files.resize(files.capacity(), -1);
+    files.resize(std::max<size_t>(7, files.size() * 2 + 1), -1);
     files[slot] = fd;
     CHECK_RET(io_uring_register_files(&ring, files.data(), files.size()),
               "io_uring_register_files");