/** * Get the archive entries in classpath as an array of Path * * @param conf Configuration that contains the classpath setting */ public static Path[] getArchiveClassPaths(Configuration conf) { String classpath = conf.get("mapred.job.classpath.archives"); if (classpath == null) return null; ArrayList list = Collections.list(new StringTokenizer(classpath, System.getProperty("path.separator"))); Path[] paths = new Path[list.size()]; for (int i = 0; i < list.size(); i++) { paths[i] = new Path((String) list.get(i)); } return paths; }
private float mean(ArrayList<Integer> l) { int t = l.size(); Integer sum = new Integer(0); for (Integer i : l) { sum += i; } return ((float) sum) / t; }
private float standard_deviation(ArrayList<Integer> l) { int t = l.size(); float ans = 0, mn = this.mean(l); for (Integer i : l) { ans += (i - mn) * (i - mn); } return (float) Math.sqrt(ans / (t - 1)); }
/** * A TaskTracker wants to know the physical locations of completed, but not yet closed, tasks. * This exists so the reduce task thread can locate map task outputs. */ public synchronized MapOutputLocation[] locateMapOutputs( String taskId, String[][] mapTasksNeeded) { ArrayList v = new ArrayList(); for (int i = 0; i < mapTasksNeeded.length; i++) { for (int j = 0; j < mapTasksNeeded[i].length; j++) { TaskInProgress tip = (TaskInProgress) taskidToTIPMap.get(mapTasksNeeded[i][j]); if (tip != null && tip.isComplete(mapTasksNeeded[i][j])) { String trackerId = (String) taskidToTrackerMap.get(mapTasksNeeded[i][j]); TaskTrackerStatus tracker; synchronized (taskTrackers) { tracker = (TaskTrackerStatus) taskTrackers.get(trackerId); } v.add(new MapOutputLocation(mapTasksNeeded[i][j], tracker.getHost(), tracker.getPort())); break; } } } // randomly shuffle results to load-balance map output requests Collections.shuffle(v); return (MapOutputLocation[]) v.toArray(new MapOutputLocation[v.size()]); }
private int median(ArrayList<Integer> l) { Collections.sort(l); int t = l.size(); return l.get(t / 2); }