/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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 org.apache.hadoop.hbase.client;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.AsyncProcessTask;
import org.apache.hadoop.hbase.client.backoff.ClientBackoffPolicy;
import org.apache.hadoop.hbase.client.backoff.ExponentialClientBackoffPolicy;
import org.apache.hadoop.hbase.client.backoff.ServerStatistics;
import org.apache.hadoop.hbase.client.coprocessor.Batch;
import org.apache.hadoop.hbase.regionserver.HRegion;
import org.apache.hadoop.hbase.regionserver.HRegionServer;
import org.apache.hadoop.hbase.regionserver.MemstoreSize;
import org.apache.hadoop.hbase.regionserver.Region;
import org.apache.hadoop.hbase.testclassification.MediumTests;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import static org.apache.hadoop.hbase.client.MetricsConnection.CLIENT_SIDE_METRICS_ENABLED_KEY;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
/**
* Test that we can actually send and use region metrics to slowdown client writes
*/
@Category(MediumTests.class)
public class TestClientPushback {
private static final Log LOG = LogFactory.getLog(TestClientPushback.class);
private static final HBaseTestingUtility UTIL = new HBaseTestingUtility();
private static final TableName tableName = TableName.valueOf("client-pushback");
private static final byte[] family = Bytes.toBytes("f");
private static final byte[] qualifier = Bytes.toBytes("q");
private static final long flushSizeBytes = 256;
@BeforeClass
public static void setupCluster() throws Exception{
Configuration conf = UTIL.getConfiguration();
// enable backpressure
conf.setBoolean(HConstants.ENABLE_CLIENT_BACKPRESSURE, true);
// use the exponential backoff policy
conf.setClass(ClientBackoffPolicy.BACKOFF_POLICY_CLASS, ExponentialClientBackoffPolicy.class,
ClientBackoffPolicy.class);
// turn the memstore size way down so we don't need to write a lot to see changes in memstore
// load
conf.setLong(HConstants.HREGION_MEMSTORE_FLUSH_SIZE, flushSizeBytes);
// ensure we block the flushes when we are double that flushsize
conf.setLong(HConstants.HREGION_MEMSTORE_BLOCK_MULTIPLIER, HConstants.DEFAULT_HREGION_MEMSTORE_BLOCK_MULTIPLIER);
conf.setBoolean(CLIENT_SIDE_METRICS_ENABLED_KEY, true);
UTIL.startMiniCluster(1);
UTIL.createTable(tableName, family);
}
@AfterClass
public static void teardownCluster() throws Exception{
UTIL.shutdownMiniCluster();
}
@Test(timeout=60000)
public void testClientTracksServerPushback() throws Exception{
Configuration conf = UTIL.getConfiguration();
ClusterConnection conn = (ClusterConnection) ConnectionFactory.createConnection(conf);
Table table = conn.getTable(tableName);
HRegionServer rs = UTIL.getHBaseCluster().getRegionServer(0);
Region region = rs.getOnlineRegions(tableName).get(0);
LOG.debug("Writing some data to "+tableName);
// write some data
Put p = new Put(Bytes.toBytes("row"));
p.addColumn(family, qualifier, Bytes.toBytes("value1"));
table.put(p);
// get the current load on RS. Hopefully memstore isn't flushed since we wrote the the data
int load = (int) ((((HRegion) region).addAndGetMemstoreSize(new MemstoreSize(0, 0)) * 100)
/ flushSizeBytes);
LOG.debug("Done writing some data to "+tableName);
// get the stats for the region hosting our table
ClientBackoffPolicy backoffPolicy = conn.getBackoffPolicy();
assertTrue("Backoff policy is not correctly configured",
backoffPolicy instanceof ExponentialClientBackoffPolicy);
ServerStatisticTracker stats = conn.getStatisticsTracker();
assertNotNull( "No stats configured for the client!", stats);
// get the names so we can query the stats
ServerName server = rs.getServerName();
byte[] regionName = region.getRegionInfo().getRegionName();
// check to see we found some load on the memstore
ServerStatistics serverStats = stats.getServerStatsForTesting(server);
ServerStatistics.RegionStatistics regionStats = serverStats.getStatsForRegion(regionName);
assertEquals("We did not find some load on the memstore", load,
regionStats.getMemstoreLoadPercent());
// check that the load reported produces a nonzero delay
long backoffTime = backoffPolicy.getBackoffTime(server, regionName, serverStats);
assertNotEquals("Reported load does not produce a backoff", backoffTime, 0);
LOG.debug("Backoff calculated for " + region.getRegionInfo().getRegionNameAsString() + " @ " +
server + " is " + backoffTime);
// Reach into the connection and submit work directly to AsyncProcess so we can
// monitor how long the submission was delayed via a callback
List<Row> ops = new ArrayList<>(1);
ops.add(p);
final CountDownLatch latch = new CountDownLatch(1);
final AtomicLong endTime = new AtomicLong();
long startTime = EnvironmentEdgeManager.currentTime();
BufferedMutatorImpl mutator = ((HTable) table).mutator;
Batch.Callback<Result> callback = (byte[] r, byte[] row, Result result) -> {
endTime.set(EnvironmentEdgeManager.currentTime());
latch.countDown();
};
AsyncProcessTask<Result> task = AsyncProcessTask.newBuilder(callback)
.setPool(mutator.getPool())
.setTableName(tableName)
.setRowAccess(ops)
.setSubmittedRows(AsyncProcessTask.SubmittedRows.AT_LEAST_ONE)
.setOperationTimeout(conn.getConnectionConfiguration().getOperationTimeout())
.setRpcTimeout(60 * 1000)
.build();
mutator.getAsyncProcess().submit(task);
// Currently the ExponentialClientBackoffPolicy under these test conditions
// produces a backoffTime of 151 milliseconds. This is long enough so the
// wait and related checks below are reasonable. Revisit if the backoff
// time reported by above debug logging has significantly deviated.
String name = server.getServerName() + "," + Bytes.toStringBinary(regionName);
MetricsConnection.RegionStats rsStats = conn.getConnectionMetrics().
serverStats.get(server).get(regionName);
assertEquals(name, rsStats.name);
assertEquals(rsStats.heapOccupancyHist.getSnapshot().getMean(),
(double)regionStats.getHeapOccupancyPercent(), 0.1 );
assertEquals(rsStats.memstoreLoadHist.getSnapshot().getMean(),
(double)regionStats.getMemstoreLoadPercent(), 0.1);
MetricsConnection.RunnerStats runnerStats = conn.getConnectionMetrics().runnerStats;
assertEquals(runnerStats.delayRunners.getCount(), 1);
assertEquals(runnerStats.normalRunners.getCount(), 1);
assertEquals("", runnerStats.delayIntevalHist.getSnapshot().getMean(),
(double)backoffTime, 0.1);
latch.await(backoffTime * 2, TimeUnit.MILLISECONDS);
assertNotEquals("AsyncProcess did not submit the work time", endTime.get(), 0);
assertTrue("AsyncProcess did not delay long enough", endTime.get() - startTime >= backoffTime);
}
@Test
public void testMutateRowStats() throws IOException {
Configuration conf = UTIL.getConfiguration();
ClusterConnection conn = (ClusterConnection) ConnectionFactory.createConnection(conf);
Table table = conn.getTable(tableName);
HRegionServer rs = UTIL.getHBaseCluster().getRegionServer(0);
Region region = rs.getOnlineRegions(tableName).get(0);
RowMutations mutations = new RowMutations(Bytes.toBytes("row"));
Put p = new Put(Bytes.toBytes("row"));
p.addColumn(family, qualifier, Bytes.toBytes("value2"));
mutations.add(p);
table.mutateRow(mutations);
ServerStatisticTracker stats = conn.getStatisticsTracker();
assertNotNull( "No stats configured for the client!", stats);
// get the names so we can query the stats
ServerName server = rs.getServerName();
byte[] regionName = region.getRegionInfo().getRegionName();
// check to see we found some load on the memstore
ServerStatistics serverStats = stats.getServerStatsForTesting(server);
ServerStatistics.RegionStatistics regionStats = serverStats.getStatsForRegion(regionName);
assertNotNull(regionStats);
assertTrue(regionStats.getMemstoreLoadPercent() > 0);
}
}