--- /dev/null	2017-11-09 09:38:01.297999907 +0100
+++ new/src/hotspot/share/jfr/recorder/repository/jfrChunkWriter.cpp	2018-04-09 15:09:21.423632921 +0200
@@ -0,0 +1,122 @@
+/*
+ * Copyright (c) 2012, 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.
+ *
+ * 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "jfr/recorder/access/jfrOptionSet.hpp"
+#include "jfr/recorder/repository/jfrChunkState.hpp"
+#include "jfr/recorder/repository/jfrChunkWriter.hpp"
+#include "jfr/utilities/jfrTraceTime.hpp"
+#include "jfr/utilities/jfrTypes.hpp"
+#include "runtime/mutexLocker.hpp"
+#include "runtime/os.hpp"
+
+const u2 JFR_VERSION_MAJOR = 1;
+const u2 JFR_VERSION_MINOR = 0;
+
+static const size_t MAGIC_LEN = 4;
+static const size_t FILEHEADER_SLOT_SIZE = 8;
+static const size_t CHUNK_SIZE_OFFSET = 8;
+
+JfrChunkWriter::JfrChunkWriter() : JfrChunkWriterBase(NULL), _chunkstate(NULL) {}
+
+bool JfrChunkWriter::initialize() {
+  assert(_chunkstate == NULL, "invariant");
+  _chunkstate = new JfrChunkState();
+  return _chunkstate != NULL;
+}
+
+static fio_fd open_existing(const char* path) {
+  return os::open(path, O_RDWR, S_IREAD | S_IWRITE);
+}
+
+static fio_fd open_chunk(const char* path) {
+  assert(JfrStream_lock->owned_by_self(), "invariant");
+  return path != NULL ? open_existing(path) : invalid_fd;
+}
+
+bool JfrChunkWriter::open() {
+  assert(_chunkstate != NULL, "invariant");
+  JfrChunkWriterBase::reset(open_chunk(_chunkstate->path()));
+  const bool is_open = this->has_valid_fd();
+  if (is_open) {
+    this->bytes("FLR", MAGIC_LEN);
+    this->be_write((u2)JFR_VERSION_MAJOR);
+    this->be_write((u2)JFR_VERSION_MINOR);
+    this->reserve(6 * FILEHEADER_SLOT_SIZE);
+    // u8 chunk_size
+    // u8 initial checkpoint offset
+    // u8 metadata section offset
+    // u8 chunk start nanos
+    // u8 chunk duration nanos
+    // u8 chunk start ticks
+    this->be_write(JfrTraceTime::frequency());
+    // chunk capabilities, CompressedIntegers etc
+    this->be_write((u4)JfrOptionSet::compressed_integers() ? 1 : 0);
+    _chunkstate->reset();
+  }
+  return is_open;
+}
+
+size_t JfrChunkWriter::close(intptr_t metadata_offset) {
+  write_header(metadata_offset);
+  this->flush();
+  this->close_fd();
+  return size_written();
+}
+
+void JfrChunkWriter::write_header(intptr_t metadata_offset) {
+  assert(this->is_valid(), "invariant");
+  // Chunk size
+  this->write_be_at_offset(size_written(), CHUNK_SIZE_OFFSET);
+  // initial checkpoint event offset
+  this->write_be_at_offset(_chunkstate->previous_checkpoint_offset(), CHUNK_SIZE_OFFSET + (1 * FILEHEADER_SLOT_SIZE));
+  // metadata event offset
+  this->write_be_at_offset(metadata_offset, CHUNK_SIZE_OFFSET + (2 * FILEHEADER_SLOT_SIZE));
+  // start of chunk in nanos since epoch
+  this->write_be_at_offset(_chunkstate->previous_start_nanos(), CHUNK_SIZE_OFFSET + (3 * FILEHEADER_SLOT_SIZE));
+  // duration of chunk in nanos
+  this->write_be_at_offset(_chunkstate->last_chunk_duration(), CHUNK_SIZE_OFFSET + (4 * FILEHEADER_SLOT_SIZE));
+  // start of chunk in ticks
+  this->write_be_at_offset(_chunkstate->previous_start_ticks(), CHUNK_SIZE_OFFSET + (5 * FILEHEADER_SLOT_SIZE));
+}
+
+void JfrChunkWriter::set_chunk_path(const char* chunk_path) {
+  _chunkstate->set_path(chunk_path);
+}
+
+intptr_t JfrChunkWriter::size_written() const {
+  return this->is_valid() ? this->current_offset() : 0;
+}
+
+intptr_t JfrChunkWriter::previous_checkpoint_offset() const {
+  return _chunkstate->previous_checkpoint_offset();
+}
+
+void JfrChunkWriter::set_previous_checkpoint_offset(intptr_t offset) {
+  _chunkstate->set_previous_checkpoint_offset(offset);
+}
+
+void JfrChunkWriter::time_stamp_chunk_now() {
+  _chunkstate->update_time_to_now();
+}