Simon MacMullen | 30f04a7 | 2020-02-05 10:57:40 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2020 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.android.server; |
| 18 | |
| 19 | import android.os.StrictMode; |
| 20 | import android.util.Slog; |
| 21 | |
| 22 | import libcore.io.IoUtils; |
| 23 | |
| 24 | import java.io.File; |
| 25 | import java.io.IOException; |
| 26 | import java.io.StringWriter; |
| 27 | |
| 28 | /** |
| 29 | * Utility method for memory pressure (PSI). |
| 30 | */ |
| 31 | public final class MemoryPressureUtil { |
| 32 | private static final String FILE = "/proc/pressure/memory"; |
| 33 | private static final String TAG = "MemoryPressure"; |
| 34 | |
| 35 | /** |
| 36 | * @return a stanza about memory PSI to add to a report. |
| 37 | */ |
| 38 | public static String currentPsiState() { |
| 39 | final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads(); |
| 40 | StringWriter contents = new StringWriter(); |
| 41 | try { |
| 42 | if (new File(FILE).exists()) { |
| 43 | contents.append("----- Output from /proc/pressure/memory -----\n"); |
| 44 | contents.append(IoUtils.readFileAsString(FILE)); |
| 45 | contents.append("----- End output from /proc/pressure/memory -----\n\n"); |
| 46 | } |
| 47 | } catch (IOException e) { |
| 48 | Slog.e(TAG, "Could not read " + FILE, e); |
| 49 | } finally { |
| 50 | StrictMode.setThreadPolicy(savedPolicy); |
| 51 | } |
| 52 | return contents.toString(); |
| 53 | } |
| 54 | |
| 55 | private MemoryPressureUtil(){} |
| 56 | } |