Each BSP task of the HAMA cluster, will print the string "Hello BSP" in serial order. This example will help you to understand the concepts of the BSP computing model.
public class SerializePrinting { public static class HelloBSP extends BSP { public static final Log LOG = LogFactory.getLog(HelloBSP.class); private Configuration conf; private final static int PRINT_INTERVAL = 5000; @Override public void bsp(BSPPeer bspPeer) throws IOException, KeeperException, InterruptedException { int num = Integer.parseInt(conf.get("bsp.peers.num")); int i = 0; for (String otherPeer : bspPeer.getAllPeerNames()) { if (bspPeer.getPeerName().equals(otherPeer)) { LOG.info("Hello BSP from " + i + " of " + num + ": " + bspPeer.getPeerName()); } Thread.sleep(PRINT_INTERVAL); bspPeer.sync(); i++; } } @Override public Configuration getConf() { return conf; } @Override public void setConf(Configuration conf) { this.conf = conf; } } public static void main(String[] args) throws InterruptedException, IOException { // BSP job configuration HamaConfiguration conf = new HamaConfiguration(); // Execute locally // conf.set("bsp.master.address", "local"); BSPJob bsp = new BSPJob(conf, SerializePrinting.class); // Set the job name bsp.setJobName("serialize printing"); bsp.setBspClass(HelloBSP.class); BSPJobClient.runJob(bsp); } } |