1 /* 2 * Copyright (C) 2011 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.am; 18 19 import java.io.FileOutputStream; 20 import java.io.IOException; 21 22 import com.android.internal.util.MemInfoReader; 23 import com.android.server.wm.WindowManagerService; 24 25 import android.graphics.Point; 26 import android.util.Slog; 27 import android.view.Display; 28 29 /** 30 * Activity manager code dealing with processes. 31 */ 32 class ProcessList { 33 // The minimum time we allow between crashes, for us to consider this 34 // application to be bad and stop and its services and reject broadcasts. 35 static final int MIN_CRASH_INTERVAL = 60*1000; 36 37 // OOM adjustments for processes in various states: 38 39 // This is a process only hosting activities that are not visible, 40 // so it can be killed without any disruption. 41 static final int HIDDEN_APP_MAX_ADJ = 15; 42 static int HIDDEN_APP_MIN_ADJ = 9; 43 44 // The B list of SERVICE_ADJ -- these are the old and decrepit 45 // services that aren't as shiny and interesting as the ones in the A list. 46 static final int SERVICE_B_ADJ = 8; 47 48 // This is the process of the previous application that the user was in. 49 // This process is kept above other things, because it is very common to 50 // switch back to the previous app. This is important both for recent 51 // task switch (toggling between the two top recent apps) as well as normal 52 // UI flow such as clicking on a URI in the e-mail app to view in the browser, 53 // and then pressing back to return to e-mail. 54 static final int PREVIOUS_APP_ADJ = 7; 55 56 // This is a process holding the home application -- we want to try 57 // avoiding killing it, even if it would normally be in the background, 58 // because the user interacts with it so much. 59 static final int HOME_APP_ADJ = 6; 60 61 // This is a process holding an application service -- killing it will not 62 // have much of an impact as far as the user is concerned. 63 static final int SERVICE_ADJ = 5; 64 65 // This is a process currently hosting a backup operation. Killing it 66 // is not entirely fatal but is generally a bad idea. 67 static final int BACKUP_APP_ADJ = 4; 68 69 // This is a process with a heavy-weight application. It is in the 70 // background, but we want to try to avoid killing it. Value set in 71 // system/rootdir/init.rc on startup. 72 static final int HEAVY_WEIGHT_APP_ADJ = 3; 73 74 // This is a process only hosting components that are perceptible to the 75 // user, and we really want to avoid killing them, but they are not 76 // immediately visible. An example is background music playback. 77 static final int PERCEPTIBLE_APP_ADJ = 2; 78 79 // This is a process only hosting activities that are visible to the 80 // user, so we'd prefer they don't disappear. 81 static final int VISIBLE_APP_ADJ = 1; 82 83 // This is the process running the current foreground app. We'd really 84 // rather not kill it! 85 static final int FOREGROUND_APP_ADJ = 0; 86 87 // This is a system persistent process, such as telephony. Definitely 88 // don't want to kill it, but doing so is not completely fatal. 89 static final int PERSISTENT_PROC_ADJ = -12; 90 91 // The system process runs at the default adjustment. 92 static final int SYSTEM_ADJ = -16; 93 94 // Memory pages are 4K. 95 static final int PAGE_SIZE = 4*1024; 96 97 // The minimum number of hidden apps we want to be able to keep around, 98 // without empty apps being able to push them out of memory. 99 static final int MIN_HIDDEN_APPS = 2; 100 101 // The maximum number of hidden processes we will keep around before 102 // killing them; this is just a control to not let us go too crazy with 103 // keeping around processes on devices with large amounts of RAM. 104 static final int MAX_HIDDEN_APPS = 24; 105 106 // We allow empty processes to stick around for at most 30 minutes. 107 static final long MAX_EMPTY_TIME = 30*60*1000; 108 109 // The number of hidden at which we don't consider it necessary to do 110 // memory trimming. 111 static final int TRIM_HIDDEN_APPS = 3; 112 113 // The number of empty apps at which we don't consider it necessary to do 114 // memory trimming. 115 static final int TRIM_EMPTY_APPS = 3; 116 117 // Threshold of number of hidden+empty where we consider memory critical. 118 static final int TRIM_CRITICAL_THRESHOLD = 3; 119 120 // Threshold of number of hidden+empty where we consider memory critical. 121 static final int TRIM_LOW_THRESHOLD = 5; 122 123 // We put empty content processes after any hidden processes that have 124 // been idle for less than 15 seconds. 125 static final long CONTENT_APP_IDLE_OFFSET = 15*1000; 126 127 // We put empty content processes after any hidden processes that have 128 // been idle for less than 120 seconds. 129 static final long EMPTY_APP_IDLE_OFFSET = 120*1000; 130 131 // These are the various interesting memory levels that we will give to 132 // the OOM killer. Note that the OOM killer only supports 6 slots, so we 133 // can't give it a different value for every possible kind of process. 134 private final int[] mOomAdj = new int[] { 135 FOREGROUND_APP_ADJ, VISIBLE_APP_ADJ, PERCEPTIBLE_APP_ADJ, 136 BACKUP_APP_ADJ, HIDDEN_APP_MIN_ADJ, HIDDEN_APP_MAX_ADJ 137 }; 138 // These are the low-end OOM level limits. This is appropriate for an 139 // HVGA or smaller phone with less than 512MB. Values are in KB. 140 private final long[] mOomMinFreeLow = new long[] { 141 8192, 12288, 16384, 142 24576, 28672, 32768 143 }; 144 // These are the high-end OOM level limits. This is appropriate for a 145 // 1280x800 or larger screen with around 1GB RAM. Values are in KB. 146 private final long[] mOomMinFreeHigh = new long[] { 147 49152, 61440, 73728, 148 86016, 98304, 122880 149 }; 150 // The actual OOM killer memory levels we are using. 151 private final long[] mOomMinFree = new long[mOomAdj.length]; 152 153 private final long mTotalMemMb; 154 155 private boolean mHaveDisplaySize; 156 157 ProcessList() { 158 MemInfoReader minfo = new MemInfoReader(); 159 minfo.readMemInfo(); 160 mTotalMemMb = minfo.getTotalSize()/(1024*1024); 161 updateOomLevels(0, 0, false); 162 } 163 164 void applyDisplaySize(WindowManagerService wm) { 165 if (!mHaveDisplaySize) { 166 Point p = new Point(); 167 wm.getInitialDisplaySize(Display.DEFAULT_DISPLAY, p); 168 if (p.x != 0 && p.y != 0) { 169 updateOomLevels(p.x, p.y, true); 170 mHaveDisplaySize = true; 171 } 172 } 173 } 174 175 private void updateOomLevels(int displayWidth, int displayHeight, boolean write) { 176 // Scale buckets from avail memory: at 300MB we use the lowest values to 177 // 700MB or more for the top values. 178 float scaleMem = ((float)(mTotalMemMb-300))/(700-300); 179 180 // Scale buckets from screen size. 181 int minSize = 320*480; // 153600 182 int maxSize = 1280*800; // 1024000 230400 870400 .264 183 float scaleDisp = ((float)(displayWidth*displayHeight)-minSize)/(maxSize-minSize); 184 //Slog.i("XXXXXX", "scaleDisp=" + scaleDisp + " dw=" + displayWidth + " dh=" + displayHeight); 185 186 StringBuilder adjString = new StringBuilder(); 187 StringBuilder memString = new StringBuilder(); 188 189 float scale = scaleMem > scaleDisp ? scaleMem : scaleDisp; 190 if (scale < 0) scale = 0; 191 else if (scale > 1) scale = 1; 192 for (int i=0; i<mOomAdj.length; i++) { 193 long low = mOomMinFreeLow[i]; 194 long high = mOomMinFreeHigh[i]; 195 mOomMinFree[i] = (long)(low + ((high-low)*scale)); 196 197 if (i > 0) { 198 adjString.append(','); 199 memString.append(','); 200 } 201 adjString.append(mOomAdj[i]); 202 memString.append((mOomMinFree[i]*1024)/PAGE_SIZE); 203 } 204 205 //Slog.i("XXXXXXX", "******************************* MINFREE: " + memString); 206 if (write) { 207 writeFile("/sys/module/lowmemorykiller/parameters/adj", adjString.toString()); 208 writeFile("/sys/module/lowmemorykiller/parameters/minfree", memString.toString()); 209 } 210 // GB: 2048,3072,4096,6144,7168,8192 211 // HC: 8192,10240,12288,14336,16384,20480 212 } 213 214 long getMemLevel(int adjustment) { 215 for (int i=0; i<mOomAdj.length; i++) { 216 if (adjustment <= mOomAdj[i]) { 217 return mOomMinFree[i] * 1024; 218 } 219 } 220 return mOomMinFree[mOomAdj.length-1] * 1024; 221 } 222 223 private void writeFile(String path, String data) { 224 FileOutputStream fos = null; 225 try { 226 fos = new FileOutputStream(path); 227 fos.write(data.getBytes()); 228 } catch (IOException e) { 229 Slog.w(ActivityManagerService.TAG, "Unable to write " + path); 230 } finally { 231 if (fos != null) { 232 try { 233 fos.close(); 234 } catch (IOException e) { 235 } 236 } 237 } 238 } 239 } 240
