1 /*
   2  * Copyright (c) 2013 Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import java.io.File;
  25 import java.io.FileWriter;
  26 import java.util.regex.Matcher;
  27 import java.util.regex.Pattern;
  28 import java.util.Arrays;
  29 import java.util.stream.Collectors;
  30 import java.lang.management.ManagementFactory;
  31 import javax.management.MalformedObjectNameException;
  32 import javax.management.ObjectName;
  33 
  34 public class NMTHelper
  35 {
  36     public static void baseline() {
  37         executeDcmd("vmNativeMemory", "baseline");
  38     }
  39 
  40     // Total: reserved=3484685KB +293KB, committed=266629KB +293KB
  41     private static Pattern totalLine = Pattern.compile("^Total: reserved=\\d+KB .*KB, committed=\\d+KB (.*)KB$");
  42 
  43     public static long committedDiff() throws Exception {
  44         String res = (String) executeDcmd("vmNativeMemory", "detail.diff");
  45         String[] lines = res.split("\n");
  46         for (String line : lines) {
  47             Matcher matcher = totalLine.matcher(line);
  48             if (matcher.matches()) {
  49                 String committed = matcher.group(1);
  50                 return Long.parseLong(committed);
  51             }
  52         }
  53         throw new Exception("Could not find the Total line in the NMT output.");
  54     }
  55 
  56     private static String executeDcmd(String cmd, String ... args) {
  57         ObjectName oname = null;
  58         try {
  59             oname = ObjectName.getInstance("com.sun.management:type=DiagnosticCommand");
  60         } catch (MalformedObjectNameException mone) {
  61             throw new RuntimeException(mone);
  62         }
  63         Object[] dcmdArgs = {args};
  64         String[] signature = {String[].class.getName()};
  65 
  66         String cmdString = cmd + " " +
  67             Arrays.stream(args).collect(Collectors.joining(" "));
  68         File f = new File("dcmdoutput-" + cmd + "-" + System.currentTimeMillis() + ".txt");
  69         System.out.println("Output from Dcmd '" + cmdString + "' is being written to file " + f);
  70         try (FileWriter fw = new FileWriter(f)) {
  71             fw.write("> " + cmdString + ":");
  72             String result = (String)ManagementFactory.getPlatformMBeanServer().
  73                     invoke(oname, cmd, dcmdArgs, signature);
  74             fw.write(result);
  75             return result;
  76         } catch(Exception ex) {
  77             ex.printStackTrace();
  78         }
  79         return null;
  80     }
  81 }