+//
+// ========================================================================
+// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
+// ------------------------------------------------------------------------
+// All rights reserved. This program and the accompanying materials
+// are made available under the terms of the Eclipse Public License v1.0
+// and Apache License v2.0 which accompanies this distribution.
+//
+// The Eclipse Public License is available at
+// http://www.eclipse.org/legal/epl-v10.html
+//
+// The Apache License v2.0 is available at
+// http://www.opensource.org/licenses/apache2.0.php
+//
+// You may elect to redistribute this code under either of these licenses.
+// ========================================================================
+//
+
+package org.eclipse.jetty.util;
+
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
+/**
+ * {@link MemoryUtils} provides an abstraction over memory properties and operations.
+ * <p />
+ */
+public class MemoryUtils
+{
+ private static final int cacheLineBytes;
+ static
+ {
+ final int defaultValue = 64;
+ int value = defaultValue;
+ try
+ {
+ value = Integer.parseInt(AccessController.doPrivileged(new PrivilegedAction<String>()
+ {
+ @Override
+ public String run()
+ {
+ return System.getProperty("org.eclipse.jetty.util.cacheLineBytes", String.valueOf(defaultValue));
+ }
+ }));
+ }
+ catch (Exception ignored)
+ {
+ }
+ cacheLineBytes = value;
+ }
+
+ private MemoryUtils()
+ {
+ }
+
+ public static int getCacheLineBytes()
+ {
+ return cacheLineBytes;
+ }
+
+ public static int getIntegersPerCacheLine()
+ {
+ return getCacheLineBytes() >> 2;
+ }
+
+ public static int getLongsPerCacheLine()
+ {
+ return getCacheLineBytes() >> 3;
+ }
+
+}