diff -r eef755718cb2 -r f527b24990d7 src/jdk.jfr/share/classes/jdk/jfr/internal/tool/Disassemble.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.jfr/share/classes/jdk/jfr/internal/tool/Disassemble.java	Wed Dec 05 16:40:12 2018 +0100
@@ -0,0 +1,250 @@
+/*
+ * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.jfr.internal.tool;
+
+import java.io.BufferedInputStream;
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.PrintStream;
+import java.nio.file.Files;
+import java.nio.file.InvalidPathException;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.List;
+
+import jdk.jfr.internal.consumer.ChunkHeader;
+import jdk.jfr.internal.consumer.RecordingInput;
+
+final class Disassemble extends Command {
+
+    @Override
+    public String getName() {
+        return "disassemble";
+    }
+
+    @Override
+    public List<String> getOptionSyntax() {
+        List<String> list = new ArrayList<>();
+        list.add("[--output <directory>]");
+        list.add("[--max-chunks <chunks>]");
+        list.add("[--max-size <size>]");
+        list.add("<file>");
+        return list;
+    }
+
+    @Override
+    public void displayOptionUsage(PrintStream stream) {
+        stream.println(" --output <directory>    The location to write the disassembled file,");
+        stream.println("                         by default the current directory");
+        stream.println("");
+        stream.println(" --max-chunks <chunks>   Maximum number of chunks per disassembled file,");
+        stream.println("                         by default 5. The chunk size varies, but is ");
+        stream.println("                         typically around 15 MB.");
+        stream.println("");
+        stream.println(" --max-size <size>       Maximum number of bytes per file.");
+        stream.println("");
+        stream.println("  <file>                 Location of the recording file (.jfr)");
+    }
+
+    @Override
+    public String getDescription() {
+        return "Disassamble a recording file into smaller files/chunks";
+    }
+
+    @Override
+    public void execute(Deque<String> options) throws UserSyntaxException, UserDataException {
+        if (options.isEmpty()) {
+            throw new UserSyntaxException("missing file");
+        }
+        Path file = getJFRInputFile(options);
+        int maxChunks = Integer.MAX_VALUE;
+        int maxsize = Integer.MAX_VALUE;
+        String output = System.getProperty("user.dir");
+        int optionCount = options.size();
+        while (optionCount > 0) {
+            if (acceptOption(options, "--output")) {
+                output = options.pop();
+            }
+            if (acceptOption(options, "--max-size")) {
+                String value = options.pop();
+                try {
+                    maxsize = Integer.parseInt(value);
+                    if (maxsize < 1) {
+                        throw new UserDataException("max size must be at least 1");
+                    }
+                } catch (NumberFormatException nfe) {
+                    throw new UserDataException("not a valid value for --max-size.");
+                }
+            }
+            if (acceptOption(options, "--max-chunks")) {
+                String value = options.pop();
+                try {
+                    maxChunks = Integer.parseInt(value);
+                    if (maxChunks < 1) {
+                        throw new UserDataException("max chunks must be at least 1.");
+                    }
+                } catch (NumberFormatException nfe) {
+                    throw new UserDataException("not a valid value for --max-size.");
+                }
+            }
+            if (optionCount == options.size()) {
+                // No progress made
+                throw new UserSyntaxException("unknown option " + options.peek());
+            }
+            optionCount = options.size();
+        }
+        Path outputPath = getDirectory(output);
+
+        println();
+        println("Examining recording " + file + " ...");
+        List<Long> sizes;
+        if (maxsize != Integer.MAX_VALUE && maxChunks == Integer.MAX_VALUE) {
+            try {
+                long fileSize = Files.size(file);
+                if (maxsize >=fileSize) {
+                    println();
+                    println("File size (" + fileSize +") does not exceed max size (" + maxsize + ")");
+                    return;
+                }
+            } catch (IOException e) {
+                throw new UserDataException("unexpected i/o error when determining file size" + e.getMessage());
+            }
+        }
+        if (maxsize == Integer.MAX_VALUE && maxChunks == Integer.MAX_VALUE) {
+            maxChunks = 5;
+        }
+
+        try {
+            sizes = findChunkSizes(file);
+        } catch (IOException e) {
+            throw new UserDataException("unexpected i/o error. " + e.getMessage());
+        }
+        if (maxsize == Integer.MAX_VALUE == sizes.size() <= maxChunks) {
+            throw new UserDataException("number of chunks in recording (" + sizes.size() + ") doesn't exceed max chunks (" + maxChunks + ")");
+        }
+        println();
+        if (sizes.size() > 0) {
+            List<Long> combinedSizes = combineChunkSizes(sizes, maxChunks, maxsize);
+            print("File consists of " + sizes.size() + " chunks. The recording will be split into ");
+            println(combinedSizes.size() + " files");
+            println();
+            splitFile(outputPath, file, combinedSizes);
+        } else {
+            throw new UserDataException("no JFR chunks found in file.");
+        }
+    }
+
+    private List<Long> findChunkSizes(Path p) throws IOException {
+        try (RecordingInput input = new RecordingInput(p.toFile())) {
+            List<Long> sizes = new ArrayList<>();
+            ChunkHeader ch = new ChunkHeader(input);
+            sizes.add(ch.getSize());
+            while (!ch.isLastChunk()) {
+                ch = ch.nextHeader();
+                sizes.add(ch.getSize());
+            }
+            return sizes;
+        }
+    }
+
+    private List<Long> combineChunkSizes(List<Long> sizes, int maxChunks, long maxSize) {
+        List<Long> reduced = new ArrayList<Long>();
+        int chunks = 1;
+        long fileSize = sizes.get(0);
+        for (int i = 1; i < sizes.size(); i++) {
+            long size = sizes.get(i);
+            if (fileSize + size > maxSize) {
+                reduced.add(fileSize);
+                chunks = 1;
+                fileSize = size;
+                continue;
+            }
+            fileSize += size;
+            if (chunks == maxChunks) {
+                reduced.add(fileSize);
+                fileSize = 0;
+                chunks = 1;
+                continue;
+            }
+            chunks++;
+        }
+        if (fileSize != 0) {
+            reduced.add(fileSize);
+        }
+        return reduced;
+    }
+
+    private void splitFile(Path directory, Path file, List<Long> splitPositions) throws UserDataException {
+        int padAmountZeros = String.valueOf(splitPositions.size() - 1).length();
+        String fileName = file.getFileName().toString();
+        String fileFormatter = fileName.subSequence(0, fileName.length() - 4) + "_%0" + padAmountZeros + "d.jfr";
+        for (int i = 0; i < splitPositions.size(); i++) {
+            String formattedFilename = String.format(fileFormatter, i);
+            try {
+                Path p = directory.resolve(formattedFilename);
+                if (Files.exists(p)) {
+                    throw new UserDataException("can't create disassembled file " + p + ", a file with that name already exist");
+                }
+            } catch (InvalidPathException ipe) {
+                throw new UserDataException("can't construct path with filename" + formattedFilename);
+            }
+        }
+
+        try (DataInputStream stream = new DataInputStream(new BufferedInputStream(new FileInputStream(file.toFile())))) {
+            for (int i = 0; i < splitPositions.size(); i++) {
+                Long l = splitPositions.get(i);
+                byte[] bytes = readBytes(stream, l.intValue());
+                String formattedFilename = String.format(fileFormatter, i);
+                Path p = directory.resolve(formattedFilename);
+                File splittedFile = p.toFile();
+                println("Writing " + splittedFile + " ... " + bytes.length);
+                FileOutputStream fos = new FileOutputStream(splittedFile);
+                fos.write(bytes);
+                fos.close();
+            }
+        } catch (IOException ioe) {
+            throw new UserDataException("i/o error writing file " + file);
+        }
+    }
+
+    private byte[] readBytes(InputStream stream, int count) throws UserDataException, IOException {
+        byte[] data = new byte[count];
+        int totalRead = 0;
+        while (totalRead < data.length) {
+            int read = stream.read(data, totalRead, data.length - totalRead);
+            if (read == -1) {
+                throw new UserDataException("unexpected end of data");
+            }
+            totalRead += read;
+        }
+        return data;
+    }
+}