/*
*
* 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 com.google.common.annotations.VisibleForTesting;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.RejectedExecutionException;
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.hbase.CallQueueTooBigException;
import org.apache.hadoop.hbase.DoNotRetryIOException;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HRegionLocation;
import org.apache.hadoop.hbase.RegionLocations;
import org.apache.hadoop.hbase.RetryImmediatelyException;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.client.backoff.ServerStatistics;
import org.apache.hadoop.hbase.client.coprocessor.Batch;
import org.apache.hadoop.hbase.exceptions.ClientExceptionsUtil;
import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
import org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.apache.htrace.Trace;
/**
* The context, and return value, for a single submit/submitAll call.
* Note on how this class (one AP submit) works. Initially, all requests are split into groups
* by server; request is sent to each server in parallel; the RPC calls are not async so a
* thread per server is used. Every time some actions fail, regions/locations might have
* changed, so we re-group them by server and region again and send these groups in parallel
* too. The result, in case of retries, is a "tree" of threads, with parent exiting after
* scheduling children. This is why lots of code doesn't require any synchronization.
*/
@InterfaceAudience.Private
class AsyncRequestFutureImpl<CResult> implements AsyncRequestFuture {
private static final Log LOG = LogFactory.getLog(AsyncRequestFutureImpl.class);
private RetryingTimeTracker tracker;
/**
* Runnable (that can be submitted to thread pool) that waits for when it's time
* to issue replica calls, finds region replicas, groups the requests by replica and
* issues the calls (on separate threads, via sendMultiAction).
* This is done on a separate thread because we don't want to wait on user thread for
* our asynchronous call, and usually we have to wait before making replica calls.
*/
private final class ReplicaCallIssuingRunnable implements Runnable {
private final long startTime;
private final List<Action> initialActions;
public ReplicaCallIssuingRunnable(List<Action> initialActions, long startTime) {
this.initialActions = initialActions;
this.startTime = startTime;
}
@Override
public void run() {
boolean done = false;
if (asyncProcess.primaryCallTimeoutMicroseconds > 0) {
try {
done = waitUntilDone(startTime * 1000L + asyncProcess.primaryCallTimeoutMicroseconds);
} catch (InterruptedException ex) {
LOG.error("Replica thread was interrupted - no replica calls: " + ex.getMessage());
return;
}
}
if (done) return; // Done within primary timeout
Map<ServerName, MultiAction> actionsByServer = new HashMap<>();
List<Action> unknownLocActions = new ArrayList<>();
if (replicaGetIndices == null) {
for (int i = 0; i < results.length; ++i) {
addReplicaActions(i, actionsByServer, unknownLocActions);
}
} else {
for (int replicaGetIndice : replicaGetIndices) {
addReplicaActions(replicaGetIndice, actionsByServer, unknownLocActions);
}
}
if (!actionsByServer.isEmpty()) {
sendMultiAction(actionsByServer, 1, null, unknownLocActions.isEmpty());
}
if (!unknownLocActions.isEmpty()) {
actionsByServer = new HashMap<>();
for (Action action : unknownLocActions) {
addReplicaActionsAgain(action, actionsByServer);
}
// Some actions may have completely failed, they are handled inside addAgain.
if (!actionsByServer.isEmpty()) {
sendMultiAction(actionsByServer, 1, null, true);
}
}
}
/**
* Add replica actions to action map by server.
* @param index Index of the original action.
* @param actionsByServer The map by server to add it to.
*/
private void addReplicaActions(int index, Map<ServerName, MultiAction> actionsByServer,
List<Action> unknownReplicaActions) {
if (results[index] != null) return; // opportunistic. Never goes from non-null to null.
Action action = initialActions.get(index);
RegionLocations loc = findAllLocationsOrFail(action, true);
if (loc == null) return;
HRegionLocation[] locs = loc.getRegionLocations();
if (locs.length == 1) {
LOG.warn("No replicas found for " + action.getAction());
return;
}
synchronized (replicaResultLock) {
// Don't run replica calls if the original has finished. We could do it e.g. if
// original has already failed before first replica call (unlikely given retries),
// but that would require additional synchronization w.r.t. returning to caller.
if (results[index] != null) return;
// We set the number of calls here. After that any path must call setResult/setError.
// True even for replicas that are not found - if we refuse to send we MUST set error.
results[index] = new ReplicaResultState(locs.length);
}
for (int i = 1; i < locs.length; ++i) {
Action replicaAction = new Action(action, i);
if (locs[i] != null) {
asyncProcess.addAction(locs[i].getServerName(), locs[i].getRegionInfo().getRegionName(),
replicaAction, actionsByServer, nonceGroup);
} else {
unknownReplicaActions.add(replicaAction);
}
}
}
private void addReplicaActionsAgain(
Action action, Map<ServerName, MultiAction> actionsByServer) {
if (action.getReplicaId() == RegionReplicaUtil.DEFAULT_REPLICA_ID) {
throw new AssertionError("Cannot have default replica here");
}
HRegionLocation loc = getReplicaLocationOrFail(action);
if (loc == null) return;
asyncProcess.addAction(loc.getServerName(), loc.getRegionInfo().getRegionName(),
action, actionsByServer, nonceGroup);
}
}
/**
* Runnable (that can be submitted to thread pool) that submits MultiAction to a
* single server. The server call is synchronous, therefore we do it on a thread pool.
*/
@VisibleForTesting
final class SingleServerRequestRunnable implements Runnable {
private final MultiAction multiAction;
private final int numAttempt;
private final ServerName server;
private final Set<CancellableRegionServerCallable> callsInProgress;
@VisibleForTesting
SingleServerRequestRunnable(
MultiAction multiAction, int numAttempt, ServerName server,
Set<CancellableRegionServerCallable> callsInProgress) {
this.multiAction = multiAction;
this.numAttempt = numAttempt;
this.server = server;
this.callsInProgress = callsInProgress;
}
@Override
public void run() {
AbstractResponse res = null;
CancellableRegionServerCallable callable = currentCallable;
try {
// setup the callable based on the actions, if we don't have one already from the request
if (callable == null) {
callable = createCallable(server, tableName, multiAction);
}
RpcRetryingCaller<AbstractResponse> caller = asyncProcess.createCaller(callable,rpcTimeout);
try {
if (callsInProgress != null) {
callsInProgress.add(callable);
}
res = caller.callWithoutRetries(callable, operationTimeout);
if (res == null) {
// Cancelled
return;
}
} catch (IOException e) {
// The service itself failed . It may be an error coming from the communication
// layer, but, as well, a functional error raised by the server.
receiveGlobalFailure(multiAction, server, numAttempt, e);
return;
} catch (Throwable t) {
// This should not happen. Let's log & retry anyway.
LOG.error("#" + asyncProcess.id + ", Caught throwable while calling. This is unexpected." +
" Retrying. Server is " + server + ", tableName=" + tableName, t);
receiveGlobalFailure(multiAction, server, numAttempt, t);
return;
}
if (res.type() == AbstractResponse.ResponseType.MULTI) {
// Normal case: we received an answer from the server, and it's not an exception.
receiveMultiAction(multiAction, server, (MultiResponse) res, numAttempt);
} else {
if (results != null) {
SingleResponse singleResponse = (SingleResponse) res;
results[0] = singleResponse.getEntry();
}
decActionCounter(1);
}
} catch (Throwable t) {
// Something really bad happened. We are on the send thread that will now die.
LOG.error("Internal AsyncProcess #" + asyncProcess.id + " error for "
+ tableName + " processing for " + server, t);
throw new RuntimeException(t);
} finally {
asyncProcess.decTaskCounters(multiAction.getRegions(), server);
if (callsInProgress != null && callable != null && res != null) {
callsInProgress.remove(callable);
}
}
}
}
private final Batch.Callback<CResult> callback;
private final BatchErrors errors;
private final ConnectionImplementation.ServerErrorTracker errorsByServer;
private final ExecutorService pool;
private final Set<CancellableRegionServerCallable> callsInProgress;
private final TableName tableName;
private final AtomicLong actionsInProgress = new AtomicLong(-1);
/**
* The lock controls access to results. It is only held when populating results where
* there might be several callers (eventual consistency gets). For other requests,
* there's one unique call going on per result index.
*/
private final Object replicaResultLock = new Object();
/**
* Result array. Null if results are not needed. Otherwise, each index corresponds to
* the action index in initial actions submitted. For most request types, has null-s for
* requests that are not done, and result/exception for those that are done.
* For eventual-consistency gets, initially the same applies; at some point, replica calls
* might be started, and ReplicaResultState is put at the corresponding indices. The
* returning calls check the type to detect when this is the case. After all calls are done,
* ReplicaResultState-s are replaced with results for the user.
*/
private final Object[] results;
/**
* Indices of replica gets in results. If null, all or no actions are replica-gets.
*/
private final int[] replicaGetIndices;
private final boolean hasAnyReplicaGets;
private final long nonceGroup;
private final CancellableRegionServerCallable currentCallable;
private final int operationTimeout;
private final int rpcTimeout;
private final AsyncProcess asyncProcess;
/**
* For {@link AsyncRequestFutureImpl#manageError(int, Row, Retry, Throwable, ServerName)}. Only
* used to make logging more clear, we don't actually care why we don't retry.
*/
public enum Retry {
YES,
NO_LOCATION_PROBLEM,
NO_NOT_RETRIABLE,
NO_RETRIES_EXHAUSTED,
NO_OTHER_SUCCEEDED
}
/** Sync point for calls to multiple replicas for the same user request (Get).
* Created and put in the results array (we assume replica calls require results) when
* the replica calls are launched. See results for details of this process.
* POJO, all fields are public. To modify them, the object itself is locked. */
private static class ReplicaResultState {
public ReplicaResultState(int callCount) {
this.callCount = callCount;
}
/** Number of calls outstanding, or 0 if a call succeeded (even with others outstanding). */
int callCount;
/** Errors for which it is not decided whether we will report them to user. If one of the
* calls succeeds, we will discard the errors that may have happened in the other calls. */
BatchErrors replicaErrors = null;
@Override
public String toString() {
return "[call count " + callCount + "; errors " + replicaErrors + "]";
}
}
public AsyncRequestFutureImpl(AsyncProcessTask task, List<Action> actions,
long nonceGroup, AsyncProcess asyncProcess) {
this.pool = task.getPool();
this.callback = task.getCallback();
this.nonceGroup = nonceGroup;
this.tableName = task.getTableName();
this.actionsInProgress.set(actions.size());
if (task.getResults() == null) {
results = task.getNeedResults() ? new Object[actions.size()] : null;
} else {
if (task.getResults().length != actions.size()) {
throw new AssertionError("results.length");
}
this.results = task.getResults();
for (int i = 0; i != this.results.length; ++i) {
results[i] = null;
}
}
List<Integer> replicaGetIndices = null;
boolean hasAnyReplicaGets = false;
if (results != null) {
// Check to see if any requests might require replica calls.
// We expect that many requests will consist of all or no multi-replica gets; in such
// cases we would just use a boolean (hasAnyReplicaGets). If there's a mix, we will
// store the list of action indexes for which replica gets are possible, and set
// hasAnyReplicaGets to true.
boolean hasAnyNonReplicaReqs = false;
int posInList = 0;
for (Action action : actions) {
boolean isReplicaGet = AsyncProcess.isReplicaGet(action.getAction());
if (isReplicaGet) {
hasAnyReplicaGets = true;
if (hasAnyNonReplicaReqs) { // Mixed case
if (replicaGetIndices == null) {
replicaGetIndices = new ArrayList<>(actions.size() - 1);
}
replicaGetIndices.add(posInList);
}
} else if (!hasAnyNonReplicaReqs) {
// The first non-multi-replica request in the action list.
hasAnyNonReplicaReqs = true;
if (posInList > 0) {
// Add all the previous requests to the index lists. We know they are all
// replica-gets because this is the first non-multi-replica request in the list.
replicaGetIndices = new ArrayList<>(actions.size() - 1);
for (int i = 0; i < posInList; ++i) {
replicaGetIndices.add(i);
}
}
}
++posInList;
}
}
this.hasAnyReplicaGets = hasAnyReplicaGets;
if (replicaGetIndices != null) {
this.replicaGetIndices = new int[replicaGetIndices.size()];
int i = 0;
for (Integer el : replicaGetIndices) {
this.replicaGetIndices[i++] = el;
}
} else {
this.replicaGetIndices = null;
}
this.callsInProgress = !hasAnyReplicaGets ? null :
Collections.newSetFromMap(
new ConcurrentHashMap<CancellableRegionServerCallable, Boolean>());
this.asyncProcess = asyncProcess;
this.errorsByServer = createServerErrorTracker();
this.errors = (asyncProcess.globalErrors != null)
? asyncProcess.globalErrors : new BatchErrors();
this.operationTimeout = task.getOperationTimeout();
this.rpcTimeout = task.getRpcTimeout();
this.currentCallable = task.getCallable();
if (task.getCallable() == null) {
tracker = new RetryingTimeTracker().start();
}
}
@VisibleForTesting
protected Set<CancellableRegionServerCallable> getCallsInProgress() {
return callsInProgress;
}
@VisibleForTesting
SingleServerRequestRunnable createSingleServerRequest(MultiAction multiAction, int numAttempt, ServerName server,
Set<CancellableRegionServerCallable> callsInProgress) {
return new SingleServerRequestRunnable(multiAction, numAttempt, server, callsInProgress);
}
/**
* Group a list of actions per region servers, and send them.
*
* @param currentActions - the list of row to submit
* @param numAttempt - the current numAttempt (first attempt is 1)
*/
void groupAndSendMultiAction(List<Action> currentActions, int numAttempt) {
Map<ServerName, MultiAction> actionsByServer = new HashMap<>();
boolean isReplica = false;
List<Action> unknownReplicaActions = null;
for (Action action : currentActions) {
RegionLocations locs = findAllLocationsOrFail(action, true);
if (locs == null) continue;
boolean isReplicaAction = !RegionReplicaUtil.isDefaultReplica(action.getReplicaId());
if (isReplica && !isReplicaAction) {
// This is the property of the current implementation, not a requirement.
throw new AssertionError("Replica and non-replica actions in the same retry");
}
isReplica = isReplicaAction;
HRegionLocation loc = locs.getRegionLocation(action.getReplicaId());
if (loc == null || loc.getServerName() == null) {
if (isReplica) {
if (unknownReplicaActions == null) {
unknownReplicaActions = new ArrayList<>(1);
}
unknownReplicaActions.add(action);
} else {
// TODO: relies on primary location always being fetched
manageLocationError(action, null);
}
} else {
byte[] regionName = loc.getRegionInfo().getRegionName();
AsyncProcess.addAction(loc.getServerName(), regionName, action, actionsByServer, nonceGroup);
}
}
boolean doStartReplica = (numAttempt == 1 && !isReplica && hasAnyReplicaGets);
boolean hasUnknown = unknownReplicaActions != null && !unknownReplicaActions.isEmpty();
if (!actionsByServer.isEmpty()) {
// If this is a first attempt to group and send, no replicas, we need replica thread.
sendMultiAction(actionsByServer, numAttempt, (doStartReplica && !hasUnknown)
? currentActions : null, numAttempt > 1 && !hasUnknown);
}
if (hasUnknown) {
actionsByServer = new HashMap<>();
for (Action action : unknownReplicaActions) {
HRegionLocation loc = getReplicaLocationOrFail(action);
if (loc == null) continue;
byte[] regionName = loc.getRegionInfo().getRegionName();
AsyncProcess.addAction(loc.getServerName(), regionName, action, actionsByServer, nonceGroup);
}
if (!actionsByServer.isEmpty()) {
sendMultiAction(
actionsByServer, numAttempt, doStartReplica ? currentActions : null, true);
}
}
}
private HRegionLocation getReplicaLocationOrFail(Action action) {
// We are going to try get location once again. For each action, we'll do it once
// from cache, because the previous calls in the loop might populate it.
int replicaId = action.getReplicaId();
RegionLocations locs = findAllLocationsOrFail(action, true);
if (locs == null) return null; // manageError already called
HRegionLocation loc = locs.getRegionLocation(replicaId);
if (loc == null || loc.getServerName() == null) {
locs = findAllLocationsOrFail(action, false);
if (locs == null) return null; // manageError already called
loc = locs.getRegionLocation(replicaId);
}
if (loc == null || loc.getServerName() == null) {
manageLocationError(action, null);
return null;
}
return loc;
}
private void manageLocationError(Action action, Exception ex) {
String msg = "Cannot get replica " + action.getReplicaId()
+ " location for " + action.getAction();
LOG.error(msg);
if (ex == null) {
ex = new IOException(msg);
}
manageError(action.getOriginalIndex(), action.getAction(),
Retry.NO_LOCATION_PROBLEM, ex, null);
}
private RegionLocations findAllLocationsOrFail(Action action, boolean useCache) {
if (action.getAction() == null) throw new IllegalArgumentException("#" + asyncProcess.id +
", row cannot be null");
RegionLocations loc = null;
try {
loc = asyncProcess.connection.locateRegion(
tableName, action.getAction().getRow(), useCache, true, action.getReplicaId());
} catch (IOException ex) {
manageLocationError(action, ex);
}
return loc;
}
/**
* Send a multi action structure to the servers, after a delay depending on the attempt
* number. Asynchronous.
*
* @param actionsByServer the actions structured by regions
* @param numAttempt the attempt number.
* @param actionsForReplicaThread original actions for replica thread; null on non-first call.
*/
void sendMultiAction(Map<ServerName, MultiAction> actionsByServer,
int numAttempt, List<Action> actionsForReplicaThread, boolean reuseThread) {
// Run the last item on the same thread if we are already on a send thread.
// We hope most of the time it will be the only item, so we can cut down on threads.
int actionsRemaining = actionsByServer.size();
// This iteration is by server (the HRegionLocation comparator is by server portion only).
for (Map.Entry<ServerName, MultiAction> e : actionsByServer.entrySet()) {
ServerName server = e.getKey();
MultiAction multiAction = e.getValue();
Collection<? extends Runnable> runnables = getNewMultiActionRunnable(server, multiAction,
numAttempt);
// make sure we correctly count the number of runnables before we try to reuse the send
// thread, in case we had to split the request into different runnables because of backoff
if (runnables.size() > actionsRemaining) {
actionsRemaining = runnables.size();
}
// run all the runnables
// HBASE-17475: Do not reuse the thread after stack reach a certain depth to prevent stack overflow
// for now, we use HConstants.DEFAULT_HBASE_CLIENT_RETRIES_NUMBER to control the depth
for (Runnable runnable : runnables) {
if ((--actionsRemaining == 0) && reuseThread
&& numAttempt % HConstants.DEFAULT_HBASE_CLIENT_RETRIES_NUMBER != 0) {
runnable.run();
} else {
try {
pool.submit(runnable);
} catch (Throwable t) {
if (t instanceof RejectedExecutionException) {
// This should never happen. But as the pool is provided by the end user,
// let's secure this a little.
LOG.warn("#" + asyncProcess.id + ", the task was rejected by the pool. This is unexpected." +
" Server is " + server.getServerName(), t);
} else {
// see #HBASE-14359 for more details
LOG.warn("Caught unexpected exception/error: ", t);
}
asyncProcess.decTaskCounters(multiAction.getRegions(), server);
// We're likely to fail again, but this will increment the attempt counter,
// so it will finish.
receiveGlobalFailure(multiAction, server, numAttempt, t);
}
}
}
}
if (actionsForReplicaThread != null) {
startWaitingForReplicaCalls(actionsForReplicaThread);
}
}
private Collection<? extends Runnable> getNewMultiActionRunnable(ServerName server,
MultiAction multiAction,
int numAttempt) {
// no stats to manage, just do the standard action
if (asyncProcess.connection.getStatisticsTracker() == null) {
if (asyncProcess.connection.getConnectionMetrics() != null) {
asyncProcess.connection.getConnectionMetrics().incrNormalRunners();
}
asyncProcess.incTaskCounters(multiAction.getRegions(), server);
SingleServerRequestRunnable runnable = createSingleServerRequest(
multiAction, numAttempt, server, callsInProgress);
return Collections.singletonList(Trace.wrap("AsyncProcess.sendMultiAction", runnable));
}
// group the actions by the amount of delay
Map<Long, DelayingRunner> actions = new HashMap<>(multiAction.size());
// split up the actions
for (Map.Entry<byte[], List<Action>> e : multiAction.actions.entrySet()) {
Long backoff = getBackoff(server, e.getKey());
DelayingRunner runner = actions.get(backoff);
if (runner == null) {
actions.put(backoff, new DelayingRunner(backoff, e));
} else {
runner.add(e);
}
}
List<Runnable> toReturn = new ArrayList<>(actions.size());
for (DelayingRunner runner : actions.values()) {
asyncProcess.incTaskCounters(runner.getActions().getRegions(), server);
String traceText = "AsyncProcess.sendMultiAction";
Runnable runnable = createSingleServerRequest(runner.getActions(), numAttempt, server, callsInProgress);
// use a delay runner only if we need to sleep for some time
if (runner.getSleepTime() > 0) {
runner.setRunner(runnable);
traceText = "AsyncProcess.clientBackoff.sendMultiAction";
runnable = runner;
if (asyncProcess.connection.getConnectionMetrics() != null) {
asyncProcess.connection.getConnectionMetrics().incrDelayRunners();
asyncProcess.connection.getConnectionMetrics().updateDelayInterval(runner.getSleepTime());
}
} else {
if (asyncProcess.connection.getConnectionMetrics() != null) {
asyncProcess.connection.getConnectionMetrics().incrNormalRunners();
}
}
runnable = Trace.wrap(traceText, runnable);
toReturn.add(runnable);
}
return toReturn;
}
/**
* @param server server location where the target region is hosted
* @param regionName name of the region which we are going to write some data
* @return the amount of time the client should wait until it submit a request to the
* specified server and region
*/
private Long getBackoff(ServerName server, byte[] regionName) {
ServerStatisticTracker tracker = asyncProcess.connection.getStatisticsTracker();
ServerStatistics stats = tracker.getStats(server);
return asyncProcess.connection.getBackoffPolicy()
.getBackoffTime(server, regionName, stats);
}
/**
* Starts waiting to issue replica calls on a different thread; or issues them immediately.
*/
private void startWaitingForReplicaCalls(List<Action> actionsForReplicaThread) {
long startTime = EnvironmentEdgeManager.currentTime();
ReplicaCallIssuingRunnable replicaRunnable = new ReplicaCallIssuingRunnable(
actionsForReplicaThread, startTime);
if (asyncProcess.primaryCallTimeoutMicroseconds == 0) {
// Start replica calls immediately.
replicaRunnable.run();
} else {
// Start the thread that may kick off replica gets.
// TODO: we could do it on the same thread, but it's a user thread, might be a bad idea.
try {
pool.submit(replicaRunnable);
} catch (RejectedExecutionException ree) {
LOG.warn("#" + asyncProcess.id + ", replica task was rejected by the pool - no replica calls", ree);
}
}
}
/**
* Check that we can retry acts accordingly: logs, set the error status.
*
* @param originalIndex the position in the list sent
* @param row the row
* @param canRetry if false, we won't retry whatever the settings.
* @param throwable the throwable, if any (can be null)
* @param server the location, if any (can be null)
* @return true if the action can be retried, false otherwise.
*/
Retry manageError(int originalIndex, Row row, Retry canRetry,
Throwable throwable, ServerName server) {
if (canRetry == Retry.YES
&& throwable != null && throwable instanceof DoNotRetryIOException) {
canRetry = Retry.NO_NOT_RETRIABLE;
}
if (canRetry != Retry.YES) {
// Batch.Callback<Res> was not called on failure in 0.94. We keep this.
setError(originalIndex, row, throwable, server);
} else if (isActionComplete(originalIndex, row)) {
canRetry = Retry.NO_OTHER_SUCCEEDED;
}
return canRetry;
}
/**
* Resubmit all the actions from this multiaction after a failure.
*
* @param rsActions the actions still to do from the initial list
* @param server the destination
* @param numAttempt the number of attempts so far
* @param t the throwable (if any) that caused the resubmit
*/
private void receiveGlobalFailure(
MultiAction rsActions, ServerName server, int numAttempt, Throwable t) {
errorsByServer.reportServerError(server);
Retry canRetry = errorsByServer.canTryMore(numAttempt)
? Retry.YES : Retry.NO_RETRIES_EXHAUSTED;
if (tableName == null && ClientExceptionsUtil.isMetaClearingException(t)) {
// tableName is null when we made a cross-table RPC call.
asyncProcess.connection.clearCaches(server);
}
int failed = 0, stopped = 0;
List<Action> toReplay = new ArrayList<>();
for (Map.Entry<byte[], List<Action>> e : rsActions.actions.entrySet()) {
byte[] regionName = e.getKey();
byte[] row = e.getValue().iterator().next().getAction().getRow();
// Do not use the exception for updating cache because it might be coming from
// any of the regions in the MultiAction.
try {
if (tableName != null) {
asyncProcess.connection.updateCachedLocations(tableName, regionName, row,
ClientExceptionsUtil.isMetaClearingException(t) ? null : t, server);
}
} catch (Throwable ex) {
// That should never happen, but if it did, we want to make sure
// we still process errors
LOG.error("Couldn't update cached region locations: " + ex);
}
for (Action action : e.getValue()) {
Retry retry = manageError(
action.getOriginalIndex(), action.getAction(), canRetry, t, server);
if (retry == Retry.YES) {
toReplay.add(action);
} else if (retry == Retry.NO_OTHER_SUCCEEDED) {
++stopped;
} else {
++failed;
}
}
}
if (toReplay.isEmpty()) {
logNoResubmit(server, numAttempt, rsActions.size(), t, failed, stopped);
} else {
resubmit(server, toReplay, numAttempt, rsActions.size(), t);
}
}
/**
* Log as much info as possible, and, if there is something to replay,
* submit it again after a back off sleep.
*/
private void resubmit(ServerName oldServer, List<Action> toReplay,
int numAttempt, int failureCount, Throwable throwable) {
// We have something to replay. We're going to sleep a little before.
// We have two contradicting needs here:
// 1) We want to get the new location after having slept, as it may change.
// 2) We want to take into account the location when calculating the sleep time.
// 3) If all this is just because the response needed to be chunked try again FAST.
// It should be possible to have some heuristics to take the right decision. Short term,
// we go for one.
boolean retryImmediately = throwable instanceof RetryImmediatelyException;
int nextAttemptNumber = retryImmediately ? numAttempt : numAttempt + 1;
long backOffTime;
if (retryImmediately) {
backOffTime = 0;
} else if (throwable instanceof CallQueueTooBigException) {
// Give a special check on CQTBE, see #HBASE-17114
backOffTime = errorsByServer.calculateBackoffTime(oldServer, asyncProcess.pauseForCQTBE);
} else {
backOffTime = errorsByServer.calculateBackoffTime(oldServer, asyncProcess.pause);
}
if (numAttempt > asyncProcess.startLogErrorsCnt) {
// We use this value to have some logs when we have multiple failures, but not too many
// logs, as errors are to be expected when a region moves, splits and so on
LOG.info(createLog(numAttempt, failureCount, toReplay.size(),
oldServer, throwable, backOffTime, true, null, -1, -1));
}
try {
if (backOffTime > 0) {
Thread.sleep(backOffTime);
}
} catch (InterruptedException e) {
LOG.warn("#" + asyncProcess.id + ", not sent: " + toReplay.size() + " operations, " + oldServer, e);
Thread.currentThread().interrupt();
return;
}
groupAndSendMultiAction(toReplay, nextAttemptNumber);
}
private void logNoResubmit(ServerName oldServer, int numAttempt,
int failureCount, Throwable throwable, int failed, int stopped) {
if (failureCount != 0 || numAttempt > asyncProcess.startLogErrorsCnt + 1) {
String timeStr = new Date(errorsByServer.getStartTrackingTime()).toString();
String logMessage = createLog(numAttempt, failureCount, 0, oldServer,
throwable, -1, false, timeStr, failed, stopped);
if (failed != 0) {
// Only log final failures as warning
LOG.warn(logMessage);
} else {
LOG.info(logMessage);
}
}
}
/**
* Called when we receive the result of a server query.
*
* @param multiAction - the multiAction we sent
* @param server - the location. It's used as a server name.
* @param responses - the response, if any
* @param numAttempt - the attempt
*/
private void receiveMultiAction(MultiAction multiAction,
ServerName server, MultiResponse responses, int numAttempt) {
assert responses != null;
// Success or partial success
// Analyze detailed results. We can still have individual failures to be redo.
// two specific throwables are managed:
// - DoNotRetryIOException: we continue to retry for other actions
// - RegionMovedException: we update the cache with the new region location
List<Action> toReplay = new ArrayList<>();
Throwable throwable = null;
int failureCount = 0;
boolean canRetry = true;
Map<byte[], MultiResponse.RegionResult> results = responses.getResults();
updateStats(server, results);
int failed = 0, stopped = 0;
// Go by original action.
for (Map.Entry<byte[], List<Action>> regionEntry : multiAction.actions.entrySet()) {
byte[] regionName = regionEntry.getKey();
Map<Integer, Object> regionResults = results.get(regionName) == null
? null : results.get(regionName).result;
if (regionResults == null) {
if (!responses.getExceptions().containsKey(regionName)) {
LOG.error("Server sent us neither results nor exceptions for "
+ Bytes.toStringBinary(regionName));
responses.getExceptions().put(regionName, new RuntimeException("Invalid response"));
}
continue;
}
boolean regionFailureRegistered = false;
for (Action sentAction : regionEntry.getValue()) {
Object result = regionResults.get(sentAction.getOriginalIndex());
// Failure: retry if it's make sense else update the errors lists
if (result == null || result instanceof Throwable) {
Row row = sentAction.getAction();
throwable = ClientExceptionsUtil.findException(result);
// Register corresponding failures once per server/once per region.
if (!regionFailureRegistered) {
regionFailureRegistered = true;
try {
asyncProcess.connection.updateCachedLocations(
tableName, regionName, row.getRow(), result, server);
} catch (Throwable ex) {
// That should never happen, but if it did, we want to make sure
// we still process errors
LOG.error("Couldn't update cached region locations: " + ex);
}
}
if (failureCount == 0) {
errorsByServer.reportServerError(server);
// We determine canRetry only once for all calls, after reporting server failure.
canRetry = errorsByServer.canTryMore(numAttempt);
}
++failureCount;
Retry retry = manageError(sentAction.getOriginalIndex(), row,
canRetry ? Retry.YES : Retry.NO_RETRIES_EXHAUSTED, (Throwable) result, server);
if (retry == Retry.YES) {
toReplay.add(sentAction);
} else if (retry == Retry.NO_OTHER_SUCCEEDED) {
++stopped;
} else {
++failed;
}
} else {
if (callback != null) {
try {
//noinspection unchecked
// TODO: would callback expect a replica region name if it gets one?
this.callback.update(regionName, sentAction.getAction().getRow(), (CResult) result);
} catch (Throwable t) {
LOG.error("User callback threw an exception for "
+ Bytes.toStringBinary(regionName) + ", ignoring", t);
}
}
setResult(sentAction, result);
}
}
}
// The failures global to a region. We will use for multiAction we sent previously to find the
// actions to replay.
for (Map.Entry<byte[], Throwable> throwableEntry : responses.getExceptions().entrySet()) {
throwable = throwableEntry.getValue();
byte[] region = throwableEntry.getKey();
List<Action> actions = multiAction.actions.get(region);
if (actions == null || actions.isEmpty()) {
throw new IllegalStateException("Wrong response for the region: " +
HRegionInfo.encodeRegionName(region));
}
if (failureCount == 0) {
errorsByServer.reportServerError(server);
canRetry = errorsByServer.canTryMore(numAttempt);
}
if (null == tableName && ClientExceptionsUtil.isMetaClearingException(throwable)) {
// For multi-actions, we don't have a table name, but we want to make sure to clear the
// cache in case there were location-related exceptions. We don't to clear the cache
// for every possible exception that comes through, however.
asyncProcess.connection.clearCaches(server);
} else {
try {
asyncProcess.connection.updateCachedLocations(
tableName, region, actions.get(0).getAction().getRow(), throwable, server);
} catch (Throwable ex) {
// That should never happen, but if it did, we want to make sure
// we still process errors
LOG.error("Couldn't update cached region locations: " + ex);
}
}
failureCount += actions.size();
for (Action action : actions) {
Row row = action.getAction();
Retry retry = manageError(action.getOriginalIndex(), row,
canRetry ? Retry.YES : Retry.NO_RETRIES_EXHAUSTED, throwable, server);
if (retry == Retry.YES) {
toReplay.add(action);
} else if (retry == Retry.NO_OTHER_SUCCEEDED) {
++stopped;
} else {
++failed;
}
}
}
if (toReplay.isEmpty()) {
logNoResubmit(server, numAttempt, failureCount, throwable, failed, stopped);
} else {
resubmit(server, toReplay, numAttempt, failureCount, throwable);
}
}
@VisibleForTesting
protected void updateStats(ServerName server, Map<byte[], MultiResponse.RegionResult> results) {
boolean metrics = asyncProcess.connection.getConnectionMetrics() != null;
boolean stats = asyncProcess.connection.getStatisticsTracker() != null;
if (!stats && !metrics) {
return;
}
for (Map.Entry<byte[], MultiResponse.RegionResult> regionStats : results.entrySet()) {
byte[] regionName = regionStats.getKey();
ClientProtos.RegionLoadStats stat = regionStats.getValue().getStat();
if (stat == null) {
LOG.error("No ClientProtos.RegionLoadStats found for server=" + server
+ ", region=" + Bytes.toStringBinary(regionName));
continue;
}
RegionLoadStats regionLoadstats = ProtobufUtil.createRegionLoadStats(stat);
ResultStatsUtil.updateStats(asyncProcess.connection.getStatisticsTracker(), server,
regionName, regionLoadstats);
ResultStatsUtil.updateStats(asyncProcess.connection.getConnectionMetrics(),
server, regionName, regionLoadstats);
}
}
private String createLog(int numAttempt, int failureCount, int replaySize, ServerName sn,
Throwable error, long backOffTime, boolean willRetry, String startTime,
int failed, int stopped) {
StringBuilder sb = new StringBuilder();
sb.append("#").append(asyncProcess.id).append(", table=").append(tableName).append(", ")
.append("attempt=").append(numAttempt)
.append("/").append(asyncProcess.numTries).append(" ");
if (failureCount > 0 || error != null){
sb.append("failed=").append(failureCount).append("ops").append(", last exception: ").
append(error == null ? "null" : error);
} else {
sb.append("succeeded");
}
sb.append(" on ").append(sn).append(", tracking started ").append(startTime);
if (willRetry) {
sb.append(", retrying after=").append(backOffTime).append("ms").
append(", replay=").append(replaySize).append("ops");
} else if (failureCount > 0) {
if (stopped > 0) {
sb.append("; not retrying ").append(stopped).append(" due to success from other replica");
}
if (failed > 0) {
sb.append("; not retrying ").append(failed).append(" - final failure");
}
}
return sb.toString();
}
/**
* Sets the non-error result from a particular action.
* @param action Action (request) that the server responded to.
* @param result The result.
*/
private void setResult(Action action, Object result) {
if (result == null) {
throw new RuntimeException("Result cannot be null");
}
ReplicaResultState state = null;
boolean isStale = !RegionReplicaUtil.isDefaultReplica(action.getReplicaId());
int index = action.getOriginalIndex();
if (results == null) {
decActionCounter(index);
return; // Simple case, no replica requests.
}
state = trySetResultSimple(index, action.getAction(), false, result, null, isStale);
if (state == null) {
return; // Simple case, no replica requests.
}
// At this point we know that state is set to replica tracking class.
// It could be that someone else is also looking at it; however, we know there can
// only be one state object, and only one thread can set callCount to 0. Other threads
// will either see state with callCount 0 after locking it; or will not see state at all
// we will replace it with the result.
synchronized (state) {
if (state.callCount == 0) {
return; // someone already set the result
}
state.callCount = 0;
}
synchronized (replicaResultLock) {
if (results[index] != state) {
throw new AssertionError("We set the callCount but someone else replaced the result");
}
results[index] = result;
}
decActionCounter(index);
}
/**
* Sets the error from a particular action.
* @param index Original action index.
* @param row Original request.
* @param throwable The resulting error.
* @param server The source server.
*/
private void setError(int index, Row row, Throwable throwable, ServerName server) {
ReplicaResultState state = null;
if (results == null) {
// Note that we currently cannot have replica requests with null results. So it shouldn't
// happen that multiple replica calls will call dAC for same actions with results == null.
// Only one call per action should be present in this case.
errors.add(throwable, row, server);
decActionCounter(index);
return; // Simple case, no replica requests.
}
state = trySetResultSimple(index, row, true, throwable, server, false);
if (state == null) {
return; // Simple case, no replica requests.
}
BatchErrors target = null; // Error will be added to final errors, or temp replica errors.
boolean isActionDone = false;
synchronized (state) {
switch (state.callCount) {
case 0: return; // someone already set the result
case 1: { // All calls failed, we are the last error.
target = errors;
isActionDone = true;
break;
}
default: {
assert state.callCount > 1;
if (state.replicaErrors == null) {
state.replicaErrors = new BatchErrors();
}
target = state.replicaErrors;
break;
}
}
--state.callCount;
}
target.add(throwable, row, server);
if (isActionDone) {
if (state.replicaErrors != null) { // last call, no need to lock
errors.merge(state.replicaErrors);
}
// See setResult for explanations.
synchronized (replicaResultLock) {
if (results[index] != state) {
throw new AssertionError("We set the callCount but someone else replaced the result");
}
results[index] = throwable;
}
decActionCounter(index);
}
}
/**
* Checks if the action is complete; used on error to prevent needless retries.
* Does not synchronize, assuming element index/field accesses are atomic.
* This is an opportunistic optimization check, doesn't have to be strict.
* @param index Original action index.
* @param row Original request.
*/
private boolean isActionComplete(int index, Row row) {
if (!AsyncProcess.isReplicaGet(row)) return false;
Object resObj = results[index];
return (resObj != null) && (!(resObj instanceof ReplicaResultState)
|| ((ReplicaResultState)resObj).callCount == 0);
}
/**
* Tries to set the result or error for a particular action as if there were no replica calls.
* @return null if successful; replica state if there were in fact replica calls.
*/
private ReplicaResultState trySetResultSimple(int index, Row row, boolean isError,
Object result, ServerName server, boolean isFromReplica) {
Object resObj = null;
if (!AsyncProcess.isReplicaGet(row)) {
if (isFromReplica) {
throw new AssertionError("Unexpected stale result for " + row);
}
results[index] = result;
} else {
synchronized (replicaResultLock) {
resObj = results[index];
if (resObj == null) {
if (isFromReplica) {
throw new AssertionError("Unexpected stale result for " + row);
}
results[index] = result;
}
}
}
ReplicaResultState rrs =
(resObj instanceof ReplicaResultState) ? (ReplicaResultState)resObj : null;
if (rrs == null && isError) {
// The resObj is not replica state (null or already set).
errors.add((Throwable)result, row, server);
}
if (resObj == null) {
// resObj is null - no replica calls were made.
decActionCounter(index);
return null;
}
return rrs;
}
private void decActionCounter(int index) {
long actionsRemaining = actionsInProgress.decrementAndGet();
if (actionsRemaining < 0) {
String error = buildDetailedErrorMsg("Incorrect actions in progress", index);
throw new AssertionError(error);
} else if (actionsRemaining == 0) {
synchronized (actionsInProgress) {
actionsInProgress.notifyAll();
}
}
}
private String buildDetailedErrorMsg(String string, int index) {
StringBuilder error = new StringBuilder(128);
error.append(string).append("; called for ").append(index).append(", actionsInProgress ")
.append(actionsInProgress.get()).append("; replica gets: ");
if (replicaGetIndices != null) {
for (int i = 0; i < replicaGetIndices.length; ++i) {
error.append(replicaGetIndices[i]).append(", ");
}
} else {
error.append(hasAnyReplicaGets ? "all" : "none");
}
error.append("; results ");
if (results != null) {
for (int i = 0; i < results.length; ++i) {
Object o = results[i];
error.append(((o == null) ? "null" : o.toString())).append(", ");
}
}
return error.toString();
}
@Override
public void waitUntilDone() throws InterruptedIOException {
try {
waitUntilDone(Long.MAX_VALUE);
} catch (InterruptedException iex) {
throw new InterruptedIOException(iex.getMessage());
} finally {
if (callsInProgress != null) {
for (CancellableRegionServerCallable clb : callsInProgress) {
clb.cancel();
}
}
}
}
private boolean waitUntilDone(long cutoff) throws InterruptedException {
boolean hasWait = cutoff != Long.MAX_VALUE;
long lastLog = EnvironmentEdgeManager.currentTime();
long currentInProgress;
while (0 != (currentInProgress = actionsInProgress.get())) {
long now = EnvironmentEdgeManager.currentTime();
if (hasWait && (now * 1000L) > cutoff) {
return false;
}
if (!hasWait) { // Only log if wait is infinite.
if (now > lastLog + 10000) {
lastLog = now;
LOG.info("#" + asyncProcess.id + ", waiting for " + currentInProgress
+ " actions to finish on table: " + tableName);
}
}
synchronized (actionsInProgress) {
if (actionsInProgress.get() == 0) break;
if (!hasWait) {
actionsInProgress.wait(10);
} else {
long waitMicroSecond = Math.min(100000L, (cutoff - now * 1000L));
TimeUnit.MICROSECONDS.timedWait(actionsInProgress, waitMicroSecond);
}
}
}
return true;
}
@Override
public boolean hasError() {
return errors.hasErrors();
}
@Override
public List<? extends Row> getFailedOperations() {
return errors.actions;
}
@Override
public RetriesExhaustedWithDetailsException getErrors() {
return errors.makeException(asyncProcess.logBatchErrorDetails);
}
@Override
public Object[] getResults() throws InterruptedIOException {
waitUntilDone();
return results;
}
/**
* Creates the server error tracker to use inside process.
* Currently, to preserve the main assumption about current retries, and to work well with
* the retry-limit-based calculation, the calculation is local per Process object.
* We may benefit from connection-wide tracking of server errors.
* @return ServerErrorTracker to use, null if there is no ServerErrorTracker on this connection
*/
private ConnectionImplementation.ServerErrorTracker createServerErrorTracker() {
return new ConnectionImplementation.ServerErrorTracker(
asyncProcess.serverTrackerTimeout, asyncProcess.numTries);
}
/**
* Create a callable. Isolated to be easily overridden in the tests.
*/
private MultiServerCallable createCallable(final ServerName server, TableName tableName,
final MultiAction multi) {
return new MultiServerCallable(asyncProcess.connection, tableName, server,
multi, asyncProcess.rpcFactory.newController(), rpcTimeout, tracker);
}
}