org.apache.hudi.org.apache.hadoop.hbase.client.MasterAddressRefresher Maven / Gradle / Ivy
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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package org.apache.hadoop.hbase.client;
import java.io.Closeable;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.apache.yetus.audience.InterfaceAudience;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
import org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProtos.ClientMetaService;
/**
* Thread safe utility that keeps master end points used by {@link MasterRegistry} up to date. This
* uses the RPC {@link ClientMetaService#getMasters} to fetch the latest list of registered masters.
* By default the refresh happens periodically (configured via
* {@link #PERIODIC_REFRESH_INTERVAL_SECS}). The refresh can also be triggered on demand via
* {@link #refreshNow()}. To prevent a flood of on-demand refreshes we expect that any attempts two
* should be spaced at least {@link #MIN_SECS_BETWEEN_REFRESHES} seconds apart.
*/
@InterfaceAudience.Private
public class MasterAddressRefresher implements Closeable {
private static final Logger LOG = LoggerFactory.getLogger(MasterAddressRefresher.class);
public static final String PERIODIC_REFRESH_INTERVAL_SECS =
"hbase.client.master_registry.refresh_interval_secs";
private static final int PERIODIC_REFRESH_INTERVAL_SECS_DEFAULT = 300;
public static final String MIN_SECS_BETWEEN_REFRESHES =
"hbase.client.master_registry.min_secs_between_refreshes";
private static final int MIN_SECS_BETWEEN_REFRESHES_DEFAULT = 60;
private final ExecutorService pool;
private final MasterRegistry registry;
private final long periodicRefreshMs;
private final long timeBetweenRefreshesMs;
private final Object refreshMasters = new Object();
@Override
public void close() {
pool.shutdownNow();
}
/**
* Thread that refreshes the master end points until it is interrupted via {@link #close()}.
* Multiple callers attempting to refresh at the same time synchronize on {@link #refreshMasters}.
*/
private class RefreshThread implements Runnable {
@Override
public void run() {
long lastRpcTs = 0;
while (!Thread.interrupted()) {
try {
// Spurious wake ups are okay, worst case we make an extra RPC call to refresh. We won't
// have duplicate refreshes because once the thread is past the wait(), notify()s are
// ignored until the thread is back to the waiting state.
synchronized (refreshMasters) {
refreshMasters.wait(periodicRefreshMs);
}
long currentTs = EnvironmentEdgeManager.currentTime();
if (lastRpcTs != 0 && currentTs - lastRpcTs <= timeBetweenRefreshesMs) {
continue;
}
lastRpcTs = currentTs;
LOG.debug("Attempting to refresh master address end points.");
Set newMasters = new HashSet<>(registry.getMasters().get());
registry.populateMasterStubs(newMasters);
LOG.debug("Finished refreshing master end points. {}", newMasters);
} catch (InterruptedException e) {
LOG.debug("Interrupted during wait, aborting refresh-masters-thread.", e);
break;
} catch (ExecutionException | IOException e) {
LOG.debug("Error populating latest list of masters.", e);
}
}
LOG.info("Master end point refresher loop exited.");
}
}
MasterAddressRefresher(Configuration conf, MasterRegistry registry) {
pool = Executors.newSingleThreadExecutor(new ThreadFactoryBuilder()
.setNameFormat("master-registry-refresh-end-points").setDaemon(true).build());
periodicRefreshMs = TimeUnit.SECONDS.toMillis(conf.getLong(PERIODIC_REFRESH_INTERVAL_SECS,
PERIODIC_REFRESH_INTERVAL_SECS_DEFAULT));
timeBetweenRefreshesMs = TimeUnit.SECONDS.toMillis(conf.getLong(MIN_SECS_BETWEEN_REFRESHES,
MIN_SECS_BETWEEN_REFRESHES_DEFAULT));
Preconditions.checkArgument(periodicRefreshMs > 0);
Preconditions.checkArgument(timeBetweenRefreshesMs < periodicRefreshMs);
this.registry = registry;
pool.submit(new RefreshThread());
}
/**
* Notifies the refresher thread to refresh the configuration. This does not guarantee a refresh.
* See class comment for details.
*/
void refreshNow() {
synchronized (refreshMasters) {
refreshMasters.notify();
}
}
}