--- old/src/share/vm/runtime/virtualspace.cpp	2012-12-13 13:49:41.000000000 +0100
+++ new/src/share/vm/runtime/virtualspace.cpp	2012-12-13 13:49:41.000000000 +0100
@@ -329,20 +329,9 @@
     if ((((size_t)base + noaccess_prefix) & (alignment - 1)) != 0) {
       // Base not aligned, retry
       if (!os::release_memory(base, size)) fatal("os::release_memory failed");
-      // Reserve size large enough to do manual alignment and
-      // increase size to a multiple of the desired alignment
+      // Make sure that size is aligned
       size = align_size_up(size, alignment);
-      size_t extra_size = size + alignment;
-      do {
-        char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
-        if (extra_base == NULL) return;
-        // Do manual alignement
-        base = (char*) align_size_up((uintptr_t) extra_base, alignment);
-        assert(base >= extra_base, "just checking");
-        // Re-reserve the region at the aligned base address.
-        os::release_memory(extra_base, extra_size);
-        base = os::reserve_memory(size, base);
-      } while (base == NULL);
+      base = os::reserve_memory_aligned(size, alignment);
 
       if (requested_address != 0 &&
           failed_to_reserve_as_requested(base, requested_address, size, false)) {