org.apache.hadoop.hbase.regionserver.AnnotationReadingPriorityFunction Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of hbase-server Show documentation
Show all versions of hbase-server Show documentation
Server functionality for HBase
/**
* 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.regionserver;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.NotServingRegionException;
import org.apache.hadoop.hbase.ipc.PriorityFunction;
import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos;
import org.apache.hadoop.hbase.protobuf.generated.RegionServerStatusProtos.ReportRegionStateTransitionRequest;
import org.apache.hadoop.hbase.protobuf.generated.RegionServerStatusProtos.RegionStateTransition;
import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.CloseRegionRequest;
import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.CompactRegionRequest;
import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.FlushRegionRequest;
import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.GetRegionInfoRequest;
import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.GetStoreFileRequest;
import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.SplitRegionRequest;
import org.apache.hadoop.hbase.protobuf.generated.ClientProtos.GetRequest;
import org.apache.hadoop.hbase.protobuf.generated.ClientProtos.MutateRequest;
import org.apache.hadoop.hbase.protobuf.generated.ClientProtos.ScanRequest;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.RegionSpecifier;
import org.apache.hadoop.hbase.protobuf.generated.RPCProtos.RequestHeader;
import org.apache.hadoop.hbase.regionserver.HRegionServer.QosPriority;
import com.google.common.annotations.VisibleForTesting;
import com.google.protobuf.Message;
import com.google.protobuf.TextFormat;
/**
* Reads special method annotations and table names to figure a priority for use by QoS facility in
* ipc; e.g: rpcs to hbase:meta get priority.
*/
// TODO: Remove. This is doing way too much work just to figure a priority. Do as Elliott
// suggests and just have the client specify a priority.
//The logic for figuring out high priority RPCs is as follows:
//1. if the method is annotated with a QosPriority of QOS_HIGH,
// that is honored
//2. parse out the protobuf message and see if the request is for meta
// region, and if so, treat it as a high priority RPC
//Some optimizations for (2) are done here -
//Clients send the argument classname as part of making the RPC. The server
//decides whether to deserialize the proto argument message based on the
//pre-established set of argument classes (knownArgumentClasses below).
//This prevents the server from having to deserialize all proto argument
//messages prematurely.
//All the argument classes declare a 'getRegion' method that returns a
//RegionSpecifier object. Methods can be invoked on the returned object
//to figure out whether it is a meta region or not.
@InterfaceAudience.Private
class AnnotationReadingPriorityFunction implements PriorityFunction {
public static final Log LOG =
LogFactory.getLog(AnnotationReadingPriorityFunction.class.getName());
private final Map annotatedQos;
//We need to mock the regionserver instance for some unit tests (set via
//setRegionServer method.
private HRegionServer hRegionServer;
@SuppressWarnings("unchecked")
private final Class[] knownArgumentClasses = new Class[]{
GetRegionInfoRequest.class,
GetStoreFileRequest.class,
CloseRegionRequest.class,
FlushRegionRequest.class,
SplitRegionRequest.class,
CompactRegionRequest.class,
GetRequest.class,
MutateRequest.class,
ScanRequest.class
};
// Some caches for helping performance
private final Map> argumentToClassMap =
new HashMap>();
private final Map, Method>> methodMap =
new HashMap, Method>>();
AnnotationReadingPriorityFunction(final HRegionServer hrs) {
this.hRegionServer = hrs;
Map qosMap = new HashMap();
for (Method m : HRegionServer.class.getMethods()) {
QosPriority p = m.getAnnotation(QosPriority.class);
if (p != null) {
// Since we protobuf'd, and then subsequently, when we went with pb style, method names
// are capitalized. This meant that this brittle compare of method names gotten by
// reflection no longer matched the method names coming in over pb. TODO: Get rid of this
// check. For now, workaround is to capitalize the names we got from reflection so they
// have chance of matching the pb ones.
String capitalizedMethodName = capitalize(m.getName());
qosMap.put(capitalizedMethodName, p.priority());
}
}
this.annotatedQos = qosMap;
if (methodMap.get("getRegion") == null) {
methodMap.put("hasRegion", new HashMap, Method>());
methodMap.put("getRegion", new HashMap, Method>());
}
for (Class cls : knownArgumentClasses) {
argumentToClassMap.put(cls.getName(), cls);
try {
methodMap.get("hasRegion").put(cls, cls.getDeclaredMethod("hasRegion"));
methodMap.get("getRegion").put(cls, cls.getDeclaredMethod("getRegion"));
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
private String capitalize(final String s) {
StringBuilder strBuilder = new StringBuilder(s);
strBuilder.setCharAt(0, Character.toUpperCase(strBuilder.charAt(0)));
return strBuilder.toString();
}
public boolean isMetaRegion(byte[] regionName) {
HRegion region;
try {
region = hRegionServer.getRegion(regionName);
} catch (NotServingRegionException ignored) {
return false;
}
return region.getRegionInfo().isMetaTable();
}
@Override
public int getPriority(RequestHeader header, Message param) {
String methodName = header.getMethodName();
Integer priorityByAnnotation = annotatedQos.get(methodName);
if (priorityByAnnotation != null) {
return priorityByAnnotation;
}
if (param == null) {
return HConstants.NORMAL_QOS;
}
// Trust the client-set priorities if set
if (header.hasPriority()) {
return header.getPriority();
}
String cls = param.getClass().getName();
Class rpcArgClass = argumentToClassMap.get(cls);
RegionSpecifier regionSpecifier = null;
//check whether the request has reference to meta region or now.
try {
// Check if the param has a region specifier; the pb methods are hasRegion and getRegion if
// hasRegion returns true. Not all listed methods have region specifier each time. For
// example, the ScanRequest has it on setup but thereafter relies on the scannerid rather than
// send the region over every time.
Method hasRegion = methodMap.get("hasRegion").get(rpcArgClass);
if (hasRegion != null && (Boolean)hasRegion.invoke(param, (Object[])null)) {
Method getRegion = methodMap.get("getRegion").get(rpcArgClass);
regionSpecifier = (RegionSpecifier)getRegion.invoke(param, (Object[])null);
HRegion region = hRegionServer.getRegion(regionSpecifier);
if (region.getRegionInfo().isMetaTable()) {
if (LOG.isTraceEnabled()) {
LOG.trace("High priority because region=" + region.getRegionNameAsString());
}
return HConstants.HIGH_QOS;
}
}
} catch (Exception ex) {
// Not good throwing an exception out of here, a runtime anyways. Let the query go into the
// server and have it throw the exception if still an issue. Just mark it normal priority.
if (LOG.isTraceEnabled()) LOG.trace("Marking normal priority after getting exception=" + ex);
return HConstants.NORMAL_QOS;
}
if (param instanceof ScanRequest) { // scanner methods...
ScanRequest request = (ScanRequest)param;
if (!request.hasScannerId()) {
return HConstants.NORMAL_QOS;
}
RegionScanner scanner = hRegionServer.getScanner(request.getScannerId());
if (scanner != null && scanner.getRegionInfo().isMetaRegion()) {
if (LOG.isTraceEnabled()) {
// Scanner requests are small in size so TextFormat version should not overwhelm log.
LOG.trace("High priority scanner request " + TextFormat.shortDebugString(request));
}
return HConstants.HIGH_QOS;
}
}
// If meta is moving then all the rest of report the report state transitions will be
// blocked. We shouldn't be in the same queue.
if (param instanceof ReportRegionStateTransitionRequest) { // Regions are moving
ReportRegionStateTransitionRequest tRequest = (ReportRegionStateTransitionRequest) param;
for (RegionStateTransition transition : tRequest.getTransitionList()) {
if (transition.getRegionInfoList() != null) {
for (HBaseProtos.RegionInfo info : transition.getRegionInfoList()) {
TableName tn = ProtobufUtil.toTableName(info.getTableName());
if (tn.isSystemTable()) {
return HConstants.HIGH_QOS;
}
}
}
}
}
return HConstants.NORMAL_QOS;
}
@VisibleForTesting
void setRegionServer(final HRegionServer hrs) {
this.hRegionServer = hrs;
}
}