| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.ddmuilib.heap; |
| |
| import com.android.ddmlib.NativeAllocationInfo; |
| import com.google.common.collect.Sets; |
| |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Set; |
| |
| /** |
| * Models a heap snapshot that is the difference between two snapshots. |
| */ |
| public class NativeHeapDiffSnapshot extends NativeHeapSnapshot { |
| private long mCommonAllocationsTotalMemory; |
| |
| public NativeHeapDiffSnapshot(NativeHeapSnapshot newSnapshot, NativeHeapSnapshot oldSnapshot) { |
| // The diff snapshots behaves like a snapshot that only contains the new allocations |
| // not present in the old snapshot |
| super(getNewAllocations(newSnapshot, oldSnapshot)); |
| |
| Set<NativeAllocationInfo> commonAllocations = |
| new HashSet<NativeAllocationInfo>(oldSnapshot.getAllocations()); |
| commonAllocations.retainAll(newSnapshot.getAllocations()); |
| |
| // Memory common between the old and new snapshots |
| mCommonAllocationsTotalMemory = getTotalMemory(commonAllocations); |
| } |
| |
| private static List<NativeAllocationInfo> getNewAllocations(NativeHeapSnapshot newSnapshot, |
| NativeHeapSnapshot oldSnapshot) { |
| Set<NativeAllocationInfo> allocations = |
| new HashSet<NativeAllocationInfo>(newSnapshot.getAllocations()); |
| |
| // compute new allocations |
| allocations.removeAll(oldSnapshot.getAllocations()); |
| |
| // Account for allocations with the same stack trace that were |
| // present in the older set of allocations. |
| // e.g. A particular stack trace might have had 3 allocations in snapshot 1, |
| // and 2 more in snapshot 2. We only want to show the new allocations (just the 2 from |
| // snapshot 2). However, the way the allocations are stored, in snapshot 2, we'll see |
| // 5 allocations at the stack trace. We need to subtract out the 3 from the first allocation |
| Set<NativeAllocationInfo> onlyInPrevious = |
| new HashSet<NativeAllocationInfo>(oldSnapshot.getAllocations()); |
| Set<NativeAllocationInfo> newAllocations = |
| Sets.newHashSetWithExpectedSize(allocations.size()); |
| |
| onlyInPrevious.removeAll(newSnapshot.getAllocations()); |
| for (NativeAllocationInfo current : allocations) { |
| NativeAllocationInfo old = getOldAllocationWithSameStack(current, onlyInPrevious); |
| if (old == null) { |
| newAllocations.add(current); |
| } else if (current.getAllocationCount() > old.getAllocationCount()) { |
| newAllocations.add(new NativeDiffAllocationInfo(current, old)); |
| } |
| } |
| |
| return new ArrayList<NativeAllocationInfo>(newAllocations); |
| } |
| |
| private static NativeAllocationInfo getOldAllocationWithSameStack( |
| NativeAllocationInfo info, |
| Set<NativeAllocationInfo> allocations) { |
| for (NativeAllocationInfo a : allocations) { |
| if (info.getSize() == a.getSize() && info.stackEquals(a)) { |
| return a; |
| } |
| } |
| |
| return null; |
| } |
| |
| @Override |
| public String getFormattedMemorySize() { |
| // for a diff snapshot, we report the following string for display: |
| // xxx bytes new allocation + yyy bytes retained from previous allocation |
| // = zzz bytes total |
| |
| long newAllocations = getTotalSize(); |
| return String.format("%s bytes new + %s bytes retained = %s bytes total", |
| formatMemorySize(newAllocations), |
| formatMemorySize(mCommonAllocationsTotalMemory), |
| formatMemorySize(newAllocations + mCommonAllocationsTotalMemory)); |
| } |
| } |