Java tutorial
/** * 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 * <p> * http://www.apache.org/licenses/LICENSE-2.0 * <p> * 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 mlbench.pagerank; import mpi.MPI; import mpi.MPIException; import mpid.core.HadoopWriter; import mpid.core.MPI_D; import mpid.core.MPI_D_Exception; import mpid.core.util.MPI_D_Constants; import mpid.util.DataMPIUtil; import mpid.util.hadoop.HadoopIOUtil; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapred.FileSplit; import org.apache.hadoop.mapred.JobConf; import org.apache.hadoop.mapred.LineRecordReader; import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat; import java.io.FileWriter; import java.io.IOException; import java.util.HashMap; /** * The Pagerank workload of DataMPI is transplanted from PEGASUS PagerankNaive. * STAGE 2: merge multiplication results. - Input: partial multiplication * results - Output: combined multiplication results */ @SuppressWarnings("deprecation") public class PagerankMerge { private static final Log LOG = LogFactory.getLog(PagerankMerge.class); private static final String MAPRED_OUTPUT_DIR = "mapreduce.output.fileoutputformat.outputdir"; private static String confPath = null; private static String inDir = null, outDir = null, maxUsedMemPercent = null, partSize = null, outFileNum = null, spillPercent = null; private static int number_nodes = 0; private static double mixing_c = 0; private static double random_coeff = 0; private static double converge_threshold = 0; @SuppressWarnings({ "rawtypes", "unchecked" }) public static void main(String[] args) throws IOException, InterruptedException { try { parseArgs(args); HashMap<String, String> conf = new HashMap<String, String>(); initConf(conf); MPI_D.Init(args, MPI_D.Mode.Common, conf); JobConf jobConf = new JobConf(confPath); if (MPI_D.COMM_BIPARTITE_O != null) { // O communicator int rank = MPI_D.Comm_rank(MPI_D.COMM_BIPARTITE_O); int size = MPI_D.Comm_size(MPI_D.COMM_BIPARTITE_O); if (rank == 0) { LOG.info(PagerankMerge.class.getSimpleName() + " O start."); } FileSplit[] inputs = DataMPIUtil.HDFSDataLocalLocator.getTaskInputs(MPI_D.COMM_BIPARTITE_O, jobConf, inDir, rank); for (int i = 0; i < inputs.length; i++) { FileSplit fsplit = inputs[i]; LineRecordReader kvrr = new LineRecordReader(jobConf, fsplit); LongWritable key = kvrr.createKey(); Text value = kvrr.createValue(); { while (kvrr.next(key, value)) { String line_text = value.toString(); final String[] line = line_text.split("\t"); if (line.length >= 2) { MPI_D.Send(new IntWritable(Integer.parseInt(line[0])), new Text(line[1])); } } } } } else if (MPI_D.COMM_BIPARTITE_A != null) { // A communicator int rank = MPI_D.Comm_rank(MPI_D.COMM_BIPARTITE_A); if (rank == 0) { LOG.info(PagerankMerge.class.getSimpleName() + " A start."); } HadoopWriter<IntWritable, Text> outrw = HadoopIOUtil.getNewWriter(jobConf, outDir, IntWritable.class, Text.class, TextOutputFormat.class, null, rank, MPI_D.COMM_BIPARTITE_A); IntWritable oldKey = null; double next_rank = 0; double previous_rank = 0; double diff = 0; int local_diffs = 0; random_coeff = (1 - mixing_c) / (double) number_nodes; converge_threshold = ((double) 1.0 / (double) number_nodes) / 10; Object[] keyValue = MPI_D.Recv(); while (keyValue != null) { IntWritable key = (IntWritable) keyValue[0]; Text value = (Text) keyValue[1]; if (oldKey == null) { oldKey = key; } if (!key.equals(oldKey)) { next_rank = next_rank * mixing_c + random_coeff; outrw.write(oldKey, new Text("v" + next_rank)); diff = Math.abs(previous_rank - next_rank); if (diff > converge_threshold) { local_diffs += 1; } oldKey = key; next_rank = 0; previous_rank = 0; } String cur_value_str = value.toString(); if (cur_value_str.charAt(0) == 's') { previous_rank = Double.parseDouble(cur_value_str.substring(1)); } else { next_rank += Double.parseDouble(cur_value_str.substring(1)); } keyValue = MPI_D.Recv(); } if (previous_rank != 0) { next_rank = next_rank * mixing_c + random_coeff; outrw.write(oldKey, new Text("v" + next_rank)); diff = Math.abs(previous_rank - next_rank); if (diff > converge_threshold) local_diffs += 1; } outrw.close(); reduceDiffs(local_diffs, rank); } MPI_D.Finalize(); } catch (MPI_D_Exception e) { e.printStackTrace(); } } private static void initConf(HashMap<String, String> conf) { conf.put(MPI_D_Constants.ReservedKeys.KEY_CLASS, org.apache.hadoop.io.IntWritable.class.getName()); conf.put(MPI_D_Constants.ReservedKeys.VALUE_CLASS, org.apache.hadoop.io.Text.class.getName()); if (maxUsedMemPercent != null) { conf.put(MPI_D_Constants.ReservedKeys.CommonModeKeys.MAX_MEM_USED_PERCENT, maxUsedMemPercent); } if (partSize != null) { conf.put(MPI_D_Constants.ReservedKeys.CommonModeKeys.BLOCK_SIZE, partSize); } if (outFileNum != null) { conf.put(MPI_D_Constants.ReservedKeys.CommonModeKeys.SEND_QUEUE_LENGTH, outFileNum); } if (spillPercent != null) { conf.put(MPI_D_Constants.ReservedKeys.CommonModeKeys.SPILL_PERCENT, spillPercent); } } private static void reduceDiffs(int local_diffs, int rank) { int diffs[] = { 0 }; int bs[] = { local_diffs }; try { MPI.COMM_WORLD.Reduce(bs, 0, diffs, 0, 1, MPI.INT, MPI.SUM, 0); MPI.COMM_WORLD.Barrier(); if (rank == 0) { LOG.info("Uncoveraged diffs:" + diffs[0]); FileWriter output = new FileWriter("var.tmp"); output.write(String.valueOf(diffs[0])); output.close(); JobConf conf = new JobConf(confPath); final FileSystem fs = FileSystem.get(conf); fs.copyFromLocalFile(true, new Path("./var.tmp"), new Path("var.tmp")); } } catch (MPIException | IOException e) { e.printStackTrace(); } } private static void parseArgs(String[] args) { if (args.length < 5) { System.err.println("ERROR: Wrong number of parameters: " + args.length + " instead of 5."); System.err.println("Usage: PagerankMerge <core-site-path> <inDir> <outDir> " + "<number_nodes>"); System.exit(-1); } else if (args.length == 5) { confPath = args[0]; inDir = args[1]; outDir = args[2]; number_nodes = Integer.parseInt(args[3]); mixing_c = Double.parseDouble(args[4]); } else if (args.length <= 9) { // Advanced Usage confPath = args[0]; inDir = args[1]; outDir = args[2]; number_nodes = Integer.parseInt(args[3]); mixing_c = Double.parseDouble(args[4]); maxUsedMemPercent = args[5]; partSize = args[6]; outFileNum = args[7]; spillPercent = args[8]; } else { System.err.println("ERROR: Error number of parameters."); System.exit(-1); } } }