Merge "Release ahat version 0.2."

3 files changed, 44 insertions, 14 deletions

diff --git a/tools/ahat/README.txt b/tools/ahat/README.txt
index 1083c2f42f..5615f8f409 100644
--- a/tools/ahat/README.txt
+++ b/tools/ahat/README.txt
@@ -10,8 +10,6 @@ Usage:
 
 TODO:
  * Add more tips to the help page.
-   - Note that only 'app' heap matters, not 'zygote' or 'image'.
-   - Say what a dex cache is.
    - Recommend how to start looking at a heap dump.
    - Say how to enable allocation sites.
    - Where to submit feedback, questions, and bug reports.
@@ -24,6 +22,7 @@ TODO:
  * Show site context and heap and class filter in "Objects" view?
  * Have a menu at the top of an object view with links to the sections?
  * Include ahat version and hprof file in the menu at the top of the page?
+ * Show root types.
  * Heaped Table
    - Make sortable by clicking on headers.
    - Use consistent order for heap columns.
@@ -86,7 +85,6 @@ Perflib Requests:
    index.
  * What's the difference between getId and getUniqueId?
  * I see objects with duplicate references.
- * Don't store stack trace by heap (CL 157252)
  * A way to get overall retained size by heap.
  * A method Instance.isReachable()
 
@@ -97,6 +95,9 @@ Things to move to perflib:
  * Computing, for each instance, the other instances it dominates.
 
 Release History:
+ 0.2 Oct 20, 2015
+   Take into account 'count' and 'offset' when displaying strings.
+
  0.1ss Aug 04, 2015
    Enable stack allocations code (using custom modified perflib).
    Sort objects in 'objects/' with default sort.
diff --git a/tools/ahat/src/AhatSnapshot.java b/tools/ahat/src/AhatSnapshot.java
index 3035ef75c9..43658f33ef 100644
--- a/tools/ahat/src/AhatSnapshot.java
+++ b/tools/ahat/src/AhatSnapshot.java
@@ -18,14 +18,12 @@ package com.android.ahat;
 
 import com.android.tools.perflib.heap.ClassObj;
 import com.android.tools.perflib.heap.Heap;
-import com.android.tools.perflib.heap.HprofParser;
 import com.android.tools.perflib.heap.Instance;
 import com.android.tools.perflib.heap.RootObj;
 import com.android.tools.perflib.heap.Snapshot;
 import com.android.tools.perflib.heap.StackFrame;
 import com.android.tools.perflib.heap.StackTrace;
-import com.android.tools.perflib.heap.io.HprofBuffer;
-import com.android.tools.perflib.heap.io.MemoryMappedFileBuffer;
+import com.android.tools.perflib.captures.MemoryMappedFileBuffer;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
 import java.io.File;
@@ -56,8 +54,7 @@ class AhatSnapshot {
    * Create an AhatSnapshot from an hprof file.
    */
   public static AhatSnapshot fromHprof(File hprof) throws IOException {
-    HprofBuffer buffer = new MemoryMappedFileBuffer(hprof);
-    Snapshot snapshot = (new HprofParser(buffer)).parse();
+    Snapshot snapshot = Snapshot.createSnapshot(new MemoryMappedFileBuffer(hprof));
     snapshot.computeDominators();
     return new AhatSnapshot(snapshot);
   }
@@ -185,20 +182,17 @@ class AhatSnapshot {
 
   // Return the stack where the given instance was allocated.
   private static StackTrace getStack(Instance inst) {
-    // TODO: return inst.getStack() once perflib is fixed.
-    return null;
+    return inst.getStack();
   }
 
   // Return the list of stack frames for a stack trace.
   private static StackFrame[] getStackFrames(StackTrace stack) {
-    // TODO: Use stack.getFrames() once perflib is fixed.
-    return null;
+    return stack.getFrames();
   }
 
   // Return the serial number of the given stack trace.
   private static int getStackTraceSerialNumber(StackTrace stack) {
-    // TODO: Use stack.getSerialNumber() once perflib is fixed.
-    return 0;
+    return stack.getSerialNumber();
   }
 
   // Get the site associated with the given stack id and depth.
diff --git a/tools/ahat/src/help.html b/tools/ahat/src/help.html
index b48d79173f..b7ae2ceb43 100644
--- a/tools/ahat/src/help.html
+++ b/tools/ahat/src/help.html
@@ -54,3 +54,38 @@ limitations under the License.
     </ul>
   </li>
 </ul>
+
+<h2>Tips:</h2>
+<h3>Heaps</h3>
+<p>
+Android heap dumps contain information for multiple heaps. The <b>app</b> heap
+is the memory used by your application. The <b>zygote</b> and <b>image</b>
+heaps are used by the system. You should ignore everything in the zygote and
+image heap and look only at the app heap. This is because changes in your
+application will not effect the zygote or image heaps, and because the zygote
+and image heaps are shared, they don't contribute significantly to your
+applications PSS.
+</p>
+
+<h3>Bitmaps</h3>
+<p>
+Bitmaps store their data using byte[] arrays. Whenever you see a large
+byte[], check if it is a bitmap by looking to see if there is a single
+android.graphics.Bitmap object referring to it. The byte[] will be marked as a
+root, but it is really being retained by the android.graphics.Bitmap object.
+</p>
+
+<h3>DexCaches</h3>
+<p>
+For each DexFile you load, there will be a corresponding DexCache whose size
+is proportional to the number of strings, fields, methods, and classes in your
+dex file. The DexCache entries may or may not be visible depending on the
+version of the Android platform the heap dump is from.
+</p>
+
+<h3>FinalizerReferences</h3>
+<p>
+A FinalizerReference is allocated for every object on the heap that has a
+non-trivial finalizer. These are stored in a linked list reachable from the
+FinalizerReference class object.
+</p>