Brian O'Connor | c67f9fa | 2014-08-07 18:17:46 -0700 | [diff] [blame] | 1 | /** |
| 2 | * Copyright 2013, Big Switch Networks, Inc. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| 5 | * not use this file except in compliance with the License. You may obtain |
| 6 | * 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, WITHOUT |
| 12 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 13 | * License for the specific language governing permissions and limitations |
| 14 | * under the License. |
| 15 | **/ |
| 16 | |
| 17 | package net.floodlightcontroller.util; |
| 18 | |
| 19 | import java.io.BufferedReader; |
| 20 | import java.io.FileInputStream; |
| 21 | import java.io.IOException; |
| 22 | import java.io.InputStreamReader; |
| 23 | import java.util.concurrent.Executors; |
| 24 | import java.util.concurrent.ScheduledExecutorService; |
| 25 | import java.util.concurrent.ScheduledFuture; |
| 26 | import java.util.concurrent.TimeUnit; |
| 27 | |
| 28 | import org.slf4j.Logger; |
| 29 | |
| 30 | import net.floodlightcontroller.core.annotations.LogMessageDocs; |
| 31 | import net.floodlightcontroller.core.annotations.LogMessageDoc; |
| 32 | |
| 33 | public class LoadMonitor implements Runnable { |
| 34 | |
| 35 | public enum LoadLevel { |
| 36 | OK, |
| 37 | HIGH, |
| 38 | VERYHIGH, |
| 39 | } |
| 40 | |
| 41 | public LoadLevel getLoadLevel() { |
| 42 | return loadlevel ; |
| 43 | } |
| 44 | |
| 45 | public double getLoad() { |
| 46 | return load ; |
| 47 | } |
| 48 | |
| 49 | public static final int LOADMONITOR_SAMPLING_INTERVAL = 1000; // mili-sec |
| 50 | public static final double THRESHOLD_HIGH = 0.90; |
| 51 | public static final double THRESHOLD_VERYHIGH = 0.95; |
| 52 | public static final int MAX_LOADED_ITERATIONS = 5; |
| 53 | public static final int MAX_LOAD_HISTORY = 5; |
| 54 | |
| 55 | protected volatile double load; |
| 56 | protected volatile LoadLevel loadlevel; |
| 57 | protected int itersLoaded; |
| 58 | |
| 59 | protected boolean isLinux; |
| 60 | protected int numcores; |
| 61 | protected int jiffyNanos; |
| 62 | protected long[] lastNanos; |
| 63 | protected long[] lastIdle; |
| 64 | protected Logger log; |
| 65 | |
| 66 | public LoadMonitor(Logger log_) { |
| 67 | log = log_; |
| 68 | loadlevel = LoadLevel.OK; |
| 69 | load = 0.0; |
| 70 | itersLoaded = 0; |
| 71 | |
| 72 | lastNanos = new long[MAX_LOAD_HISTORY]; |
| 73 | lastIdle = new long[MAX_LOAD_HISTORY]; |
| 74 | for (int i=0 ; i<MAX_LOAD_HISTORY ; i++) { |
| 75 | lastNanos[i] = 0L; |
| 76 | lastIdle[i] = 0L; |
| 77 | } |
| 78 | |
| 79 | isLinux = System.getProperty("os.name").equals("Linux"); |
| 80 | numcores = 1; |
| 81 | jiffyNanos = 10 * 1000 * 1000; |
| 82 | if (isLinux) { |
| 83 | try { |
| 84 | numcores = Integer.parseInt( |
| 85 | this.runcmd("/usr/bin/nproc")); |
| 86 | jiffyNanos = (1000 * 1000 * 1000) / Integer.parseInt( |
| 87 | this.runcmd("/usr/bin/getconf CLK_TCK")); |
| 88 | } |
| 89 | catch (NumberFormatException ex) { |
| 90 | if (log != null) { |
| 91 | // Log message documented on runcmd function |
| 92 | log.error("Exception in inializing load monitor ", ex); |
| 93 | } |
| 94 | else { |
| 95 | ex.printStackTrace(); |
| 96 | } |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | @Override |
| 102 | @LogMessageDocs({ |
| 103 | @LogMessageDoc( |
| 104 | message="System under very heavy load, dropping some packet-ins", |
| 105 | explanation="We detcted that the system was under very heavy" + |
| 106 | " load, dropping some packet-ins temporarily"), |
| 107 | @LogMessageDoc( |
| 108 | message="System under heavy load, dropping some new flows", |
| 109 | explanation="We detcted that the system was under heavy load," + |
| 110 | " dropping some new flows temporarily") |
| 111 | }) |
| 112 | public void run() { |
| 113 | if (!isLinux) return; |
| 114 | |
| 115 | long currNanos = System.nanoTime(); |
| 116 | long currIdle = this.readIdle(); |
| 117 | for (int i=0 ; i < (MAX_LOAD_HISTORY - 1) ; i++) { |
| 118 | lastNanos[i] = lastNanos[i+1]; |
| 119 | lastIdle[i] = lastIdle[i+1]; |
| 120 | } |
| 121 | lastNanos[MAX_LOAD_HISTORY - 1] = currNanos; |
| 122 | lastIdle[MAX_LOAD_HISTORY - 1] = currIdle; |
| 123 | |
| 124 | if (itersLoaded >= MAX_LOADED_ITERATIONS) { |
| 125 | loadlevel = LoadLevel.OK; |
| 126 | itersLoaded = 0; |
| 127 | return; |
| 128 | } |
| 129 | |
| 130 | long nanos = lastNanos[MAX_LOAD_HISTORY - 1] - lastNanos[0]; |
| 131 | long idle = lastIdle[MAX_LOAD_HISTORY - 1] - lastIdle[0]; |
| 132 | load = |
| 133 | 1.0 - ((double)(idle * jiffyNanos) / (double)(nanos * numcores)); |
| 134 | |
| 135 | if (load > THRESHOLD_VERYHIGH) { |
| 136 | loadlevel = LoadLevel.VERYHIGH; |
| 137 | itersLoaded += 1; |
| 138 | String msg = "System under very heavy load, dropping packet-ins."; |
| 139 | |
| 140 | if (log != null) { |
| 141 | log.error(msg); |
| 142 | } |
| 143 | else { |
| 144 | System.out.println(msg); |
| 145 | } |
| 146 | return; |
| 147 | } |
| 148 | |
| 149 | if (load > THRESHOLD_HIGH) { |
| 150 | loadlevel = LoadLevel.HIGH; |
| 151 | itersLoaded += 1; |
| 152 | String msg = "System under heavy load, dropping new flows."; |
| 153 | |
| 154 | if (log != null) { |
| 155 | log.error(msg); |
| 156 | } |
| 157 | else { |
| 158 | System.out.println(msg); |
| 159 | } |
| 160 | return; |
| 161 | } |
| 162 | |
| 163 | loadlevel = LoadLevel.OK; |
| 164 | itersLoaded = 0; |
| 165 | return; |
| 166 | } |
| 167 | |
| 168 | @LogMessageDoc( |
| 169 | message="Exception in reading load monitor params, using defaults", |
| 170 | explanation="There was an error in inializing load monitor's props," + |
| 171 | " using default parameters") |
| 172 | protected String runcmd(String cmd) { |
| 173 | String line; |
| 174 | StringBuilder ret = new StringBuilder(); |
| 175 | try { |
| 176 | Process p = Runtime.getRuntime().exec(cmd); |
| 177 | BufferedReader input = |
| 178 | new BufferedReader( |
| 179 | new InputStreamReader(p.getInputStream())); |
| 180 | while ((line = input.readLine()) != null) { |
| 181 | ret.append(line); |
| 182 | } |
| 183 | input.close(); |
| 184 | p.waitFor(); |
| 185 | } |
| 186 | catch (InterruptedException ex) { |
| 187 | if (log != null) { |
| 188 | log.error("Exception in inializing load monitor ", ex); |
| 189 | } |
| 190 | else { |
| 191 | ex.printStackTrace(); |
| 192 | } |
| 193 | } |
| 194 | catch (IOException ex) { |
| 195 | if (log != null) { |
| 196 | log.error("Exception in inializing load monitor ", ex); |
| 197 | } |
| 198 | else { |
| 199 | ex.printStackTrace(); |
| 200 | } |
| 201 | } |
| 202 | return ret.toString(); |
| 203 | |
| 204 | } |
| 205 | |
| 206 | protected long readIdle() { |
| 207 | long idle = 0; |
| 208 | FileInputStream fs = null; |
| 209 | BufferedReader reader = null; |
| 210 | try { |
| 211 | try { |
| 212 | fs = new FileInputStream("/proc/stat"); |
| 213 | reader = new BufferedReader(new InputStreamReader(fs)); |
| 214 | String line = reader.readLine(); |
| 215 | if (line == null) throw new IOException("Empty file"); |
| 216 | idle = Long.parseLong(line.split("\\s+")[4]); |
| 217 | } finally { |
| 218 | if (reader != null) |
| 219 | reader.close(); |
| 220 | if (fs != null) |
| 221 | fs.close(); |
| 222 | } |
| 223 | } catch (IOException ex) { |
| 224 | log.error("Error reading idle time from /proc/stat", ex); |
| 225 | } |
| 226 | return idle; |
| 227 | |
| 228 | } |
| 229 | |
| 230 | public ScheduledFuture<?> startMonitoring(ScheduledExecutorService ses) |
| 231 | { |
| 232 | ScheduledFuture<?> monitorTask = |
| 233 | ses.scheduleAtFixedRate( |
| 234 | this, 0, |
| 235 | LOADMONITOR_SAMPLING_INTERVAL, TimeUnit.MILLISECONDS); |
| 236 | return monitorTask; |
| 237 | } |
| 238 | |
| 239 | /* |
| 240 | * For testing |
| 241 | */ |
| 242 | public ScheduledFuture<?> printMonitoring(ScheduledExecutorService ses) |
| 243 | { |
| 244 | final LoadMonitor mon = this; |
| 245 | ScheduledFuture<?> monitorTask = |
| 246 | ses.scheduleAtFixedRate( |
| 247 | new Runnable() { |
| 248 | public void run() { |
| 249 | System.out.println(mon.getLoad()); |
| 250 | } |
| 251 | }, LOADMONITOR_SAMPLING_INTERVAL/2, |
| 252 | LOADMONITOR_SAMPLING_INTERVAL, TimeUnit.MILLISECONDS); |
| 253 | return monitorTask; |
| 254 | } |
| 255 | |
| 256 | public static void main(String[] args) { |
| 257 | final LoadMonitor monitor = new LoadMonitor(null); |
| 258 | final ScheduledExecutorService scheduler = |
| 259 | Executors.newScheduledThreadPool(1); |
| 260 | final ScheduledFuture<?> monitorTask = |
| 261 | monitor.startMonitoring(scheduler); |
| 262 | final ScheduledFuture<?> printTask = |
| 263 | monitor.printMonitoring(scheduler); |
| 264 | |
| 265 | // Run the tasks for 2 minutes |
| 266 | scheduler.schedule( |
| 267 | new Runnable() { |
| 268 | public void run() { |
| 269 | monitorTask.cancel(true); |
| 270 | printTask.cancel(true); |
| 271 | } |
| 272 | }, 5*60, TimeUnit.SECONDS); |
| 273 | } |
| 274 | |
| 275 | } |