2 // ========================================================================
3 // Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
4 // ------------------------------------------------------------------------
5 // All rights reserved. This program and the accompanying materials
6 // are made available under the terms of the Eclipse Public License v1.0
7 // and Apache License v2.0 which accompanies this distribution.
9 // The Eclipse Public License is available at
10 // http://www.eclipse.org/legal/epl-v10.html
12 // The Apache License v2.0 is available at
13 // http://www.opensource.org/licenses/apache2.0.php
15 // You may elect to redistribute this code under either of these licenses.
16 // ========================================================================
19 package org.eclipse.jetty.util;
21 import java.security.AccessController;
22 import java.security.PrivilegedAction;
25 * {@link MemoryUtils} provides an abstraction over memory properties and operations.
28 public class MemoryUtils
30 private static final int cacheLineBytes;
33 final int defaultValue = 64;
34 int value = defaultValue;
37 value = Integer.parseInt(AccessController.doPrivileged(new PrivilegedAction<String>()
42 return System.getProperty("org.eclipse.jetty.util.cacheLineBytes", String.valueOf(defaultValue));
46 catch (Exception ignored)
49 cacheLineBytes = value;
56 public static int getCacheLineBytes()
58 return cacheLineBytes;
61 public static int getIntegersPerCacheLine()
63 return getCacheLineBytes() >> 2;
66 public static int getLongsPerCacheLine()
68 return getCacheLineBytes() >> 3;