package org.apache.hadoop.chukwa.datacollection.collector;
import junit.framework.TestCase;
import org.apache.hadoop.chukwa.datacollection.agent.ChukwaAgent;
import org.apache.hadoop.chukwa.datacollection.collector.servlet.ServletCollector;
import org.apache.hadoop.chukwa.datacollection.connector.http.HttpConnector;
import org.apache.hadoop.chukwa.datacollection.sender.RetryListOfCollectors;
import org.apache.hadoop.chukwa.datacollection.writer.NullWriter;
import org.apache.hadoop.chukwa.datacollection.writer.PipelineStageWriter;
import org.apache.hadoop.chukwa.util.ConstRateAdaptor;
import org.apache.hadoop.conf.Configuration;
import org.mortbay.jetty.Server;
import org.mortbay.jetty.servlet.Context;
import org.mortbay.jetty.servlet.ServletHolder;
public class TestBackpressure extends TestCase {
int PORTNO = 9991;
/**
* NOTE THAT WRITE-RATE * POST SIZE MUST BE GREATER THAN TEST DURATION
*
* Default max post size is 2 MB; need to process that several times during test.
*/
int TEST_DURATION_SECS = 40;
int WRITE_RATE_KB = 200; //kb/sec
int SEND_RATE = 2500* 1000; //bytes/sec
int MIN_ACCEPTABLE_PERCENT = 60;
public void testBackpressure() throws Exception {
Configuration conf = new Configuration();
conf.set("chukwaCollector.writerClass", NullWriter.class
.getCanonicalName());
conf.set(NullWriter.RATE_OPT_NAME, ""+WRITE_RATE_KB);//kb/sec
conf.setInt(HttpConnector.MIN_POST_INTERVAL_OPT, 100);
conf.setInt("constAdaptor.sleepVariance", 1);
conf.setInt("constAdaptor.minSleep", 50);
conf.setInt("chukwaAgent.control.port", 0);
ChukwaAgent agent = new ChukwaAgent(conf);
RetryListOfCollectors clist = new RetryListOfCollectors(conf);
clist.add("http://localhost:"+PORTNO+"/chukwa");
HttpConnector conn = new HttpConnector(agent);
conn.setCollectors(clist);
conn.start();
Server server = new Server(PORTNO);
Context root = new Context(server, "/", Context.SESSIONS);
root.addServlet(new ServletHolder(new ServletCollector(conf)), "/*");
server.start();
server.setStopAtShutdown(false);
Thread.sleep(1000);
agent.processAddCommand("add constSend = " + ConstRateAdaptor.class.getCanonicalName() +
" testData "+ SEND_RATE + " 0");
assertNotNull(agent.getAdaptor("constSend"));
Thread.sleep(TEST_DURATION_SECS * 1000);
String[] stat = agent.getAdaptorList().get("constSend").split(" ");
long kbytesPerSec = Long.valueOf(stat[stat.length -1]) / TEST_DURATION_SECS / 1000;
System.out.println("data rate was " + kbytesPerSec + " kb /second");
assertTrue(kbytesPerSec < WRITE_RATE_KB); //write rate should throttle sends
assertTrue(kbytesPerSec > MIN_ACCEPTABLE_PERCENT* WRITE_RATE_KB / 100);//an assumption, but should hold true
agent.shutdown();
}
}