diff -r 5d043a159d5c -r 53dccc90a5be src/jdk.jfr/share/classes/jdk/jfr/consumer/EventSetLocation.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.jfr/share/classes/jdk/jfr/consumer/EventSetLocation.java	Fri May 17 18:03:14 2019 +0200
@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) 2019, 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.consumer;
+
+import java.io.IOException;
+import java.nio.file.DirectoryStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.TreeMap;
+
+import jdk.jfr.internal.LogLevel;
+import jdk.jfr.internal.LogTag;
+import jdk.jfr.internal.Logger;
+import jdk.jfr.internal.Repository;
+import jdk.jfr.internal.consumer.ChunkHeader;
+
+/**
+ * This class corresponds to a disk repository.
+ * <p>
+ * Main purpose is to act as a cache if multiple {@code EventStream} want to
+ * access the same repository. An {@code EventSetLocation} should be released
+ * when it is no longer being used.
+ *
+ */
+final class EventSetLocation {
+    private static Map<Path, EventSetLocation> locations = new HashMap<>();
+
+    private final SortedMap<Long, EventSet> eventSets = new TreeMap<>();
+    private final Map<Path, Long> lastPaths = new HashMap<>();
+
+    final Path path;
+    private int count = 0;
+    private volatile boolean closed;
+
+    private EventSetLocation(Path path) {
+        this.path = path;
+    }
+
+    public static EventSetLocation get(Path absolutPath) {
+        synchronized (locations) {
+            EventSetLocation esl = locations.get(absolutPath);
+            if (esl == null) {
+                esl = new EventSetLocation(absolutPath);
+                locations.put(absolutPath, esl);
+            }
+            esl.count++;
+            return esl;
+        }
+    }
+
+    public static EventSetLocation current() throws IOException {
+        Repository.getRepository().ensureRepository();
+        return get(Repository.getRepository().getRepositoryPath().toPath());
+    }
+
+    public void release() {
+        synchronized (locations) {
+            count--;
+            if (count == 0) {
+                locations.remove(path);
+                closed = true;
+            }
+        }
+    }
+
+    public synchronized EventSet acquire(long startTimeNanos, EventSet previousEventSet) {
+        synchronized (eventSets) {
+            while (!closed) {
+                SortedMap<Long, EventSet> after = eventSets.tailMap(startTimeNanos);
+                if (!after.isEmpty()) {
+                    EventSet es =  after.get(after.firstKey());
+                    Logger.log(LogTag.JFR_SYSTEM_STREAMING, LogLevel.TRACE, "Acquired " + startTimeNanos + ", got " + es);
+                    es.acquire();
+                    return es;
+                }
+                try {
+                    updateEventSets(previousEventSet);
+                } catch (IOException e) {
+                    e.printStackTrace();
+                    // This can happen if a chunk is being removed
+                    // between the file was discovered and an instance
+                    // of an EventSet was constructed. Just ignore,
+                    // and retry later.
+                }
+                try {
+                    eventSets.wait(1000);
+                } catch (InterruptedException e) {
+                    // ignore
+                }
+            }
+        }
+        return null;
+    }
+
+    private void updateEventSets(EventSet previousEventSet) throws IOException {
+        List<Path> added = new ArrayList<>();
+        Set<Path> current = new HashSet<>();
+        try (DirectoryStream<Path> dirStream = Files.newDirectoryStream(path, "*.jfr")) {
+            for (Path p : dirStream) {
+                if (!lastPaths.containsKey(p)) {
+                    added.add(p);
+                    Logger.log(LogTag.JFR_SYSTEM_STREAMING, LogLevel.DEBUG, "New file found: " + p.toAbsolutePath());
+                }
+                current.add(p);
+            }
+        }
+        List<Path> removed = new ArrayList<>();
+        for (Path p : lastPaths.keySet()) {
+            if (!current.contains(p)) {
+                removed.add(p);
+            }
+        }
+
+        for (Path remove : removed) {
+            Long time = lastPaths.get(remove);
+            eventSets.remove(time);
+            lastPaths.remove(remove);
+        }
+        Collections.sort(added, (p1,p2) -> p1.compareTo(p2));
+        for (Path p : added) {
+            // Only add files that have a complete header
+            // as the JVM may be in progress writing the file
+            long size = Files.size(p);
+            if (size >= ChunkHeader.HEADER_SIZE) {
+                EventSet es = new EventSet(this, previousEventSet, p);
+                long startTime = es.getStartTimeNanos();
+                if (startTime == 0) {
+                    String errorMsg = "Chunk header should always contain a valid start time";
+                    System.err.println(errorMsg);
+                    throw new InternalError(errorMsg);
+                }
+                EventSet previous = eventSets.get(startTime);
+                if (previous != null) {
+                    String errorMsg = "Found chunk " + p + " with the same start time " + startTime + " as previous chunk " + previous.getPath();
+                    System.err.println(errorMsg);
+                    throw new InternalError(errorMsg);
+                }
+                eventSets.put(startTime, es);
+                lastPaths.put(p, startTime);
+                previousEventSet = es;
+            }
+        }
+    }
+}