--- a/src/share/vm/runtime/arguments.cpp	Fri May 10 11:27:55 2013 -0700
+++ b/src/share/vm/runtime/arguments.cpp	Mon May 13 07:53:45 2013 +0200
@@ -2100,6 +2100,26 @@
 #endif
   }
 
+  // Need to limit the extent of the padding to reasonable size.
+  // 8K is well beyond the reasonable HW cache line size, even with the
+  // aggressive prefetching, while still leaving the room for segregating
+  // among the distinct pages.
+  if (ContendedPaddingWidth < 0 || ContendedPaddingWidth > 8192) {
+    jio_fprintf(defaultStream::error_stream(),
+                "ContendedPaddingWidth=" INTX_FORMAT " must be the between %d and %d\n",
+                ContendedPaddingWidth, 0, 8192);
+    status = false;
+  }
+
+  // Need to enforce the padding not to break the existing field alignments.
+  // It is sufficient to check against the largest type size.
+  if ((ContendedPaddingWidth % BytesPerLong) != 0) {
+    jio_fprintf(defaultStream::error_stream(),
+                "ContendedPaddingWidth=" INTX_FORMAT " must be the multiple of %d\n",
+                ContendedPaddingWidth, BytesPerLong);
+    status = false;
+  }
+
   return status;
 }
 
@@ -3097,36 +3117,27 @@
 }
 
 void Arguments::set_shared_spaces_flags() {
-  const bool must_share = DumpSharedSpaces || RequireSharedSpaces;
-  const bool might_share = must_share || UseSharedSpaces;
-
-  // CompressedOops cannot be used with CDS.  The offsets of oopmaps and
-  // static fields are incorrect in the archive.  With some more clever
-  // initialization, this restriction can probably be lifted.
-  // ??? UseLargePages might be okay now
-  const bool cannot_share = UseCompressedOops ||
-                            (UseLargePages && FLAG_IS_CMDLINE(UseLargePages));
-  if (cannot_share) {
-    if (must_share) {
-        warning("disabling large pages %s"
-                "because of %s", "" LP64_ONLY("and compressed oops "),
-                DumpSharedSpaces ? "-Xshare:dump" : "-Xshare:on");
-        FLAG_SET_CMDLINE(bool, UseLargePages, false);
-        LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedOops, false));
-        LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedKlassPointers, false));
-    } else {
-      // Prefer compressed oops and large pages to class data sharing
-      if (UseSharedSpaces && Verbose) {
-        warning("turning off use of shared archive because of large pages%s",
-                 "" LP64_ONLY(" and/or compressed oops"));
+#ifdef _LP64
+    const bool must_share = DumpSharedSpaces || RequireSharedSpaces;
+
+    // CompressedOops cannot be used with CDS.  The offsets of oopmaps and
+    // static fields are incorrect in the archive.  With some more clever
+    // initialization, this restriction can probably be lifted.
+    if (UseCompressedOops) {
+      if (must_share) {
+          warning("disabling compressed oops because of %s",
+                  DumpSharedSpaces ? "-Xshare:dump" : "-Xshare:on");
+          FLAG_SET_CMDLINE(bool, UseCompressedOops, false);
+          FLAG_SET_CMDLINE(bool, UseCompressedKlassPointers, false);
+      } else {
+        // Prefer compressed oops to class data sharing
+        if (UseSharedSpaces && Verbose) {
+          warning("turning off use of shared archive because of compressed oops");
+        }
+        no_shared_spaces();
       }
-      no_shared_spaces();
     }
-  } else if (UseLargePages && might_share) {
-    // Disable large pages to allow shared spaces.  This is sub-optimal, since
-    // there may not even be a shared archive to use.
-    FLAG_SET_DEFAULT(UseLargePages, false);
-  }
+#endif
 
   if (DumpSharedSpaces) {
     if (RequireSharedSpaces) {