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Posted to commits@hbase.apache.org by st...@apache.org on 2015/05/13 17:24:17 UTC
hbase git commit: HBASE-13071 Hbase Streaming Scan Feature
Repository: hbase
Updated Branches:
refs/heads/master 220ac141b -> 86b91997d
HBASE-13071 Hbase Streaming Scan Feature
Signed-off-by: stack <st...@apache.org>
Project: http://git-wip-us.apache.org/repos/asf/hbase/repo
Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/86b91997
Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/86b91997
Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/86b91997
Branch: refs/heads/master
Commit: 86b91997d0590fcf00634e9e90216e77da607fd2
Parents: 220ac14
Author: eshcar <es...@yahoo-inc.com>
Authored: Sun May 10 11:11:44 2015 +0300
Committer: stack <st...@apache.org>
Committed: Wed May 13 08:23:39 2015 -0700
----------------------------------------------------------------------
.../client/ClientAsyncPrefetchScanner.java | 234 +++++++++++++++++++
.../hadoop/hbase/client/ClientScanner.java | 59 +++--
.../hbase/client/ClientSimpleScanner.java | 54 +++++
.../hadoop/hbase/client/ClientSmallScanner.java | 13 +-
.../org/apache/hadoop/hbase/client/HTable.java | 17 +-
.../hbase/client/ReversedClientScanner.java | 2 +-
.../org/apache/hadoop/hbase/client/Scan.java | 30 ++-
.../hadoop/hbase/client/TableConfiguration.java | 14 +-
.../hadoop/hbase/client/TestClientScanner.java | 10 +
.../client/TestClientSmallReversedScanner.java | 32 ++-
.../hbase/client/TestClientSmallScanner.java | 34 ++-
.../client/TestScannersFromClientSide.java | 49 ++++
12 files changed, 481 insertions(+), 67 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientAsyncPrefetchScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientAsyncPrefetchScanner.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientAsyncPrefetchScanner.java
new file mode 100644
index 0000000..c4eb478
--- /dev/null
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientAsyncPrefetchScanner.java
@@ -0,0 +1,234 @@
+/**
+ * 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 org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.classification.InterfaceAudience;
+import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
+import org.apache.hadoop.hbase.util.Threads;
+
+import java.io.IOException;
+import java.util.Queue;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * ClientAsyncPrefetchScanner implements async scanner behaviour.
+ * Specifically, the cache used by this scanner is a concurrent queue which allows both
+ * the producer (hbase client) and consumer (application) to access the queue in parallel.
+ * The number of rows returned in a prefetch is defined by the caching factor and the result size
+ * factor.
+ * This class allocates a buffer cache, whose size is a function of both factors.
+ * The prefetch is invoked when the cache is halfÂfilled, instead of waiting for it to be empty.
+ * This is defined in the method {@link ClientAsyncPrefetchScanner#prefetchCondition()}.
+ */
+@InterfaceAudience.Private
+public class ClientAsyncPrefetchScanner extends ClientScanner {
+
+ private static final int ESTIMATED_SINGLE_RESULT_SIZE = 1024;
+ private static final int DEFAULT_QUEUE_CAPACITY = 1024;
+
+ private int cacheCapacity;
+ private AtomicLong cacheSizeInBytes;
+ // exception queue (from prefetch to main scan execution)
+ private Queue<Exception> exceptionsQueue;
+ // prefetch runnable object to be executed asynchronously
+ private PrefetchRunnable prefetchRunnable;
+ // Boolean flag to ensure only a single prefetch is running (per scan)
+ // We use atomic boolean to allow multiple concurrent threads to
+ // consume records from the same cache, but still have a single prefetcher thread.
+ // For a single consumer thread this can be replace with a native boolean.
+ private AtomicBoolean prefetchRunning;
+ // an attribute for synchronizing close between scanner and prefetch threads
+ private AtomicLong closingThreadId;
+ private static final int NO_THREAD = -1;
+
+ public ClientAsyncPrefetchScanner(Configuration configuration, Scan scan, TableName name,
+ ClusterConnection connection, RpcRetryingCallerFactory rpcCallerFactory,
+ RpcControllerFactory rpcControllerFactory, ExecutorService pool,
+ int replicaCallTimeoutMicroSecondScan) throws IOException {
+ super(configuration, scan, name, connection, rpcCallerFactory, rpcControllerFactory, pool,
+ replicaCallTimeoutMicroSecondScan);
+ }
+
+ @Override
+ protected void initCache() {
+ // concurrent cache
+ cacheCapacity = calcCacheCapacity();
+ cache = new LinkedBlockingQueue<Result>(cacheCapacity);
+ cacheSizeInBytes = new AtomicLong(0);
+ exceptionsQueue = new ConcurrentLinkedQueue<Exception>();
+ prefetchRunnable = new PrefetchRunnable();
+ prefetchRunning = new AtomicBoolean(false);
+ closingThreadId = new AtomicLong(NO_THREAD);
+ }
+
+ @Override
+ public Result next() throws IOException {
+
+ try {
+ handleException();
+
+ // If the scanner is closed and there's nothing left in the cache, next is a no-op.
+ if (getCacheCount() == 0 && this.closed) {
+ return null;
+ }
+ if (prefetchCondition()) {
+ // run prefetch in the background only if no prefetch is already running
+ if (!isPrefetchRunning()) {
+ if (prefetchRunning.compareAndSet(false, true)) {
+ getPool().execute(prefetchRunnable);
+ }
+ }
+ }
+
+ while (isPrefetchRunning()) {
+ // prefetch running or still pending
+ if (getCacheCount() > 0) {
+ Result res = cache.poll();
+ long estimatedSize = calcEstimatedSize(res);
+ addEstimatedSize(-estimatedSize);
+ return res;
+ } else {
+ // (busy) wait for a record - sleep
+ Threads.sleep(1);
+ }
+ }
+
+ if (getCacheCount() > 0) {
+ return cache.poll();
+ }
+
+ // if we exhausted this scanner before calling close, write out the scan metrics
+ writeScanMetrics();
+ return null;
+ } finally {
+ handleException();
+ }
+ }
+
+ @Override
+ public void close() {
+ if (!scanMetricsPublished) writeScanMetrics();
+ closed = true;
+ if (!isPrefetchRunning()) {
+ if(closingThreadId.compareAndSet(NO_THREAD, Thread.currentThread().getId())) {
+ super.close();
+ }
+ } // else do nothing since the async prefetch still needs this resources
+ }
+
+ @Override
+ public int getCacheCount() {
+ if(cache != null) {
+ int size = cache.size();
+ if(size > cacheCapacity) {
+ cacheCapacity = size;
+ }
+ return size;
+ } else {
+ return 0;
+ }
+ }
+
+ @Override
+ protected void addEstimatedSize(long estimatedSize) {
+ cacheSizeInBytes.addAndGet(estimatedSize);
+ }
+
+ private void handleException() throws IOException {
+ //The prefetch task running in the background puts any exception it
+ //catches into this exception queue.
+ // Rethrow the exception so the application can handle it.
+ while (!exceptionsQueue.isEmpty()) {
+ Exception first = exceptionsQueue.peek();
+ first.printStackTrace();
+ if (first instanceof IOException) {
+ throw (IOException) first;
+ }
+ throw (RuntimeException) first;
+ }
+ }
+
+ private boolean isPrefetchRunning() {
+ return prefetchRunning.get();
+ }
+
+ // double buffer - double cache size
+ private int calcCacheCapacity() {
+ int capacity = Integer.MAX_VALUE;
+ if(caching > 0 && caching < (Integer.MAX_VALUE /2)) {
+ capacity = caching * 2 + 1;
+ }
+ if(capacity == Integer.MAX_VALUE){
+ if(maxScannerResultSize != Integer.MAX_VALUE) {
+ capacity = (int) (maxScannerResultSize / ESTIMATED_SINGLE_RESULT_SIZE);
+ }
+ else {
+ capacity = DEFAULT_QUEUE_CAPACITY;
+ }
+ }
+ return capacity;
+ }
+
+ private boolean prefetchCondition() {
+ return
+ (getCacheCount() < getCountThreshold()) &&
+ (maxScannerResultSize == Long.MAX_VALUE ||
+ getCacheSizeInBytes() < getSizeThreshold()) ;
+ }
+
+ private int getCountThreshold() {
+ return cacheCapacity / 2 ;
+ }
+
+ private long getSizeThreshold() {
+ return maxScannerResultSize / 2 ;
+ }
+
+ private long getCacheSizeInBytes() {
+ return cacheSizeInBytes.get();
+ }
+
+
+ private class PrefetchRunnable implements Runnable {
+
+ @Override
+ public void run() {
+ try {
+ loadCache();
+ } catch (Exception e) {
+ exceptionsQueue.add(e);
+ } finally {
+ prefetchRunning.set(false);
+ if(closed) {
+ if (closingThreadId.compareAndSet(NO_THREAD, Thread.currentThread().getId())) {
+ // close was waiting for the prefetch to end
+ close();
+ }
+ }
+ }
+ }
+
+ }
+
+}
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
index 1ea8769..566bf4b 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientScanner.java
@@ -17,14 +17,7 @@
*/
package org.apache.hadoop.hbase.client;
-import java.io.IOException;
-import java.io.InterruptedIOException;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-
+import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
@@ -45,7 +38,14 @@ import org.apache.hadoop.hbase.protobuf.generated.MapReduceProtos;
import org.apache.hadoop.hbase.regionserver.RegionServerStoppedException;
import org.apache.hadoop.hbase.util.Bytes;
-import com.google.common.annotations.VisibleForTesting;
+import java.io.IOException;
+import java.io.InterruptedIOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+import java.util.concurrent.ExecutorService;
/**
* Implements the scanner interface for the HBase client.
@@ -53,7 +53,7 @@ import com.google.common.annotations.VisibleForTesting;
* through them all.
*/
@InterfaceAudience.Private
-public class ClientScanner extends AbstractClientScanner {
+public abstract class ClientScanner extends AbstractClientScanner {
private static final Log LOG = LogFactory.getLog(ClientScanner.class);
// A byte array in which all elements are the max byte, and it is used to
// construct closest front row
@@ -64,7 +64,7 @@ public class ClientScanner extends AbstractClientScanner {
// wonky: e.g. if it splits on us.
protected HRegionInfo currentRegion = null;
protected ScannerCallableWithReplicas callable = null;
- protected final LinkedList<Result> cache = new LinkedList<Result>();
+ protected Queue<Result> cache;
/**
* A list of partial results that have been returned from the server. This list should only
* contain results if this scanner does not have enough partial results to form the complete
@@ -151,9 +151,12 @@ public class ClientScanner extends AbstractClientScanner {
this.rpcControllerFactory = controllerFactory;
this.conf = conf;
+ initCache();
initializeScannerInConstruction();
}
+ protected abstract void initCache();
+
protected void initializeScannerInConstruction() throws IOException{
// initialize the scanner
nextScanner(this.caching, false);
@@ -342,8 +345,11 @@ public class ClientScanner extends AbstractClientScanner {
scanMetricsPublished = true;
}
- @Override
- public Result next() throws IOException {
+ protected void initSyncCache() {
+ cache = new LinkedList<Result>();
+ }
+
+ protected Result nextWithSyncCache() throws IOException {
// If the scanner is closed and there's nothing left in the cache, next is a no-op.
if (cache.size() == 0 && this.closed) {
return null;
@@ -370,6 +376,8 @@ public class ClientScanner extends AbstractClientScanner {
* Contact the servers to load more {@link Result}s in the cache.
*/
protected void loadCache() throws IOException {
+ // check if scanner was closed during previous prefetch
+ if (closed) return;
Result[] values = null;
long remainingResultSize = maxScannerResultSize;
int countdown = this.caching;
@@ -482,11 +490,10 @@ public class ClientScanner extends AbstractClientScanner {
if (!resultsToAddToCache.isEmpty()) {
for (Result rs : resultsToAddToCache) {
cache.add(rs);
- // We don't make Iterator here
- for (Cell cell : rs.rawCells()) {
- remainingResultSize -= CellUtil.estimatedHeapSizeOf(cell);
- }
+ long estimatedHeapSizeOfResult = calcEstimatedSize(rs);
countdown--;
+ remainingResultSize -= estimatedHeapSizeOfResult;
+ addEstimatedSize(estimatedHeapSizeOfResult);
this.lastResult = rs;
}
}
@@ -532,6 +539,24 @@ public class ClientScanner extends AbstractClientScanner {
return remainingResultSize > 0 && remainingRows > 0 && !regionHasMoreResults;
}
+ protected long calcEstimatedSize(Result rs) {
+ long estimatedHeapSizeOfResult = 0;
+ // We don't make Iterator here
+ for (Cell cell : rs.rawCells()) {
+ estimatedHeapSizeOfResult += CellUtil.estimatedHeapSizeOf(cell);
+ }
+ return estimatedHeapSizeOfResult;
+ }
+
+ protected void addEstimatedSize(long estimatedHeapSizeOfResult) {
+ return;
+ }
+
+ @VisibleForTesting
+ public int getCacheCount() {
+ return cache != null ? cache.size() : 0;
+ }
+
/**
* This method ensures all of our book keeping regarding partial results is kept up to date. This
* method should be called once we know that the results we received back from the RPC request do
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSimpleScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSimpleScanner.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSimpleScanner.java
new file mode 100644
index 0000000..3998ac0
--- /dev/null
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSimpleScanner.java
@@ -0,0 +1,54 @@
+/**
+ * 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 org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.classification.InterfaceAudience;
+import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
+
+import java.io.IOException;
+import java.util.LinkedList;
+import java.util.concurrent.ExecutorService;
+
+/**
+ * ClientSimpleScanner implements a sync scanner behaviour.
+ * The cache is a simple list.
+ * The prefetch is invoked only when the application finished processing the entire cache.
+ */
+@InterfaceAudience.Private
+public class ClientSimpleScanner extends ClientScanner {
+
+ public ClientSimpleScanner(Configuration configuration, Scan scan, TableName name,
+ ClusterConnection connection, RpcRetryingCallerFactory rpcCallerFactory,
+ RpcControllerFactory rpcControllerFactory, ExecutorService pool,
+ int replicaCallTimeoutMicroSecondScan) throws IOException {
+ super(configuration, scan, name, connection, rpcCallerFactory, rpcControllerFactory, pool,
+ replicaCallTimeoutMicroSecondScan);
+ }
+
+ @Override
+ protected void initCache() {
+ initSyncCache();
+ }
+
+ @Override
+ public Result next() throws IOException {
+ return nextWithSyncCache();
+ }
+}
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSmallScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSmallScanner.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSmallScanner.java
index e959e27..f9bdd55 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSmallScanner.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ClientSmallScanner.java
@@ -18,10 +18,8 @@
*/
package org.apache.hadoop.hbase.client;
-import java.io.IOException;
-import java.io.InterruptedIOException;
-import java.util.concurrent.ExecutorService;
-
+import com.google.common.annotations.VisibleForTesting;
+import com.google.protobuf.ServiceException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
@@ -39,8 +37,9 @@ import org.apache.hadoop.hbase.protobuf.generated.ClientProtos.ScanRequest;
import org.apache.hadoop.hbase.protobuf.generated.ClientProtos.ScanResponse;
import org.apache.hadoop.hbase.util.Bytes;
-import com.google.common.annotations.VisibleForTesting;
-import com.google.protobuf.ServiceException;
+import java.io.IOException;
+import java.io.InterruptedIOException;
+import java.util.concurrent.ExecutorService;
/**
* Client scanner for small scan. Generally, only one RPC is called to fetch the
@@ -50,7 +49,7 @@ import com.google.protobuf.ServiceException;
* For small scan, it will get better performance than {@link ClientScanner}
*/
@InterfaceAudience.Private
-public class ClientSmallScanner extends ClientScanner {
+public class ClientSmallScanner extends ClientSimpleScanner {
private static final Log LOG = LogFactory.getLog(ClientSmallScanner.class);
private ScannerCallableWithReplicas smallScanCallable = null;
private SmallScannerCallableFactory callableFactory;
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HTable.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HTable.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HTable.java
index 324fe61..6ba0b87 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HTable.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/HTable.java
@@ -620,6 +620,11 @@ public class HTable implements HTableInterface {
scan.setMaxResultSize(scannerMaxResultSize);
}
+ Boolean async = scan.isAsyncPrefetch();
+ if (async == null) {
+ async = tableConfiguration.isClientScannerAsyncPrefetch();
+ }
+
if (scan.isReversed()) {
if (scan.isSmall()) {
return new ClientSmallReversedScanner(getConfiguration(), scan, getName(),
@@ -637,9 +642,15 @@ public class HTable implements HTableInterface {
this.connection, this.rpcCallerFactory, this.rpcControllerFactory,
pool, tableConfiguration.getReplicaCallTimeoutMicroSecondScan());
} else {
- return new ClientScanner(getConfiguration(), scan, getName(), this.connection,
- this.rpcCallerFactory, this.rpcControllerFactory,
- pool, tableConfiguration.getReplicaCallTimeoutMicroSecondScan());
+ if (async) {
+ return new ClientAsyncPrefetchScanner(getConfiguration(), scan, getName(), this.connection,
+ this.rpcCallerFactory, this.rpcControllerFactory,
+ pool, tableConfiguration.getReplicaCallTimeoutMicroSecondScan());
+ } else {
+ return new ClientSimpleScanner(getConfiguration(), scan, getName(), this.connection,
+ this.rpcCallerFactory, this.rpcControllerFactory,
+ pool, tableConfiguration.getReplicaCallTimeoutMicroSecondScan());
+ }
}
}
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ReversedClientScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ReversedClientScanner.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ReversedClientScanner.java
index ef4b89d..dde82ba 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ReversedClientScanner.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ReversedClientScanner.java
@@ -35,7 +35,7 @@ import org.apache.hadoop.hbase.util.ExceptionUtil;
* A reversed client scanner which support backward scanning
*/
@InterfaceAudience.Private
-public class ReversedClientScanner extends ClientScanner {
+public class ReversedClientScanner extends ClientSimpleScanner {
private static final Log LOG = LogFactory.getLog(ReversedClientScanner.class);
/**
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
index 3b6194f..0b51150 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java
@@ -145,8 +145,23 @@ public class Scan extends Query {
private Map<byte [], NavigableSet<byte []>> familyMap =
new TreeMap<byte [], NavigableSet<byte []>>(Bytes.BYTES_COMPARATOR);
private Boolean loadColumnFamiliesOnDemand = null;
+ private Boolean asyncPrefetch = null;
/**
+ * Parameter name for client scanner sync/async prefetch toggle.
+ * When using async scanner, prefetching data from the server is done at the background.
+ * The parameter currently won't have any effect in the case that the user has set
+ * Scan#setSmall or Scan#setReversed
+ */
+ public static final String HBASE_CLIENT_SCANNER_ASYNC_PREFETCH =
+ "hbase.client.scanner.async.prefetch";
+
+ /**
+ * Default value of {@link #HBASE_CLIENT_SCANNER_ASYNC_PREFETCH}.
+ */
+ public static final boolean DEFAULT_HBASE_CLIENT_SCANNER_ASYNC_PREFETCH = false;
+
+ /**
* Set it true for small scan to get better performance
*
* Small scan should use pread and big scan can use seek + read
@@ -255,6 +270,7 @@ public class Scan extends Query {
this.tr = get.getTimeRange();
this.familyMap = get.getFamilyMap();
this.getScan = true;
+ this.asyncPrefetch = false;
this.consistency = get.getConsistency();
for (Map.Entry<String, byte[]> attr : get.getAttributesMap().entrySet()) {
setAttribute(attr.getKey(), attr.getValue());
@@ -971,4 +987,16 @@ public class Scan extends Query {
if (bytes == null) return null;
return ProtobufUtil.toScanMetrics(bytes);
}
-}
\ No newline at end of file
+
+
+ public Boolean isAsyncPrefetch() {
+ return asyncPrefetch;
+ }
+
+ public Scan setAsyncPrefetch(boolean asyncPrefetch) {
+ this.asyncPrefetch = asyncPrefetch;
+ return this;
+ }
+
+
+}
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/main/java/org/apache/hadoop/hbase/client/TableConfiguration.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/TableConfiguration.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/TableConfiguration.java
index 901e86d..1113cfd 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/TableConfiguration.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/TableConfiguration.java
@@ -43,7 +43,10 @@ public class TableConfiguration {
private final int retries;
private final int maxKeyValueSize;
- /**
+ // toggle for async/sync prefetch
+ private final boolean clientScannerAsyncPrefetch;
+
+ /**
* Constructor
* @param conf Configuration object
*/
@@ -73,6 +76,9 @@ public class TableConfiguration {
this.retries = conf.getInt(
HConstants.HBASE_CLIENT_RETRIES_NUMBER, HConstants.DEFAULT_HBASE_CLIENT_RETRIES_NUMBER);
+ this.clientScannerAsyncPrefetch = conf.getBoolean(
+ Scan.HBASE_CLIENT_SCANNER_ASYNC_PREFETCH, Scan.DEFAULT_HBASE_CLIENT_SCANNER_ASYNC_PREFETCH);
+
this.maxKeyValueSize = conf.getInt(MAX_KEYVALUE_SIZE_KEY, MAX_KEYVALUE_SIZE_DEFAULT);
}
@@ -91,6 +97,7 @@ public class TableConfiguration {
this.primaryCallTimeoutMicroSecond = 10000;
this.replicaCallTimeoutMicroSecondScan = 1000000;
this.retries = HConstants.DEFAULT_HBASE_CLIENT_RETRIES_NUMBER;
+ this.clientScannerAsyncPrefetch = Scan.DEFAULT_HBASE_CLIENT_SCANNER_ASYNC_PREFETCH;
this.maxKeyValueSize = MAX_KEYVALUE_SIZE_DEFAULT;
}
@@ -129,4 +136,9 @@ public class TableConfiguration {
public long getScannerMaxResultSize() {
return scannerMaxResultSize;
}
+
+ public boolean isClientScannerAsyncPrefetch() {
+ return clientScannerAsyncPrefetch;
+ }
+
}
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientScanner.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientScanner.java
index a91def3..3f406df 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientScanner.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientScanner.java
@@ -23,6 +23,7 @@ import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
import java.io.IOException;
+import java.util.LinkedList;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
@@ -121,6 +122,15 @@ public class TestClientScanner {
public void setRpcFinished(boolean rpcFinished) {
this.rpcFinished = rpcFinished;
}
+
+ @Override
+ protected void initCache() {
+ initSyncCache();
+ }
+
+ @Override public Result next() throws IOException {
+ return nextWithSyncCache();
+ }
}
@Test
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallReversedScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallReversedScanner.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallReversedScanner.java
index 4611d08..082090e 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallReversedScanner.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallReversedScanner.java
@@ -17,23 +17,9 @@
*/
package org.apache.hadoop.hbase.client;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
-import java.io.IOException;
-import java.nio.charset.StandardCharsets;
-import java.util.Iterator;
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-
import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.HRegionInfo;
-import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.KeyValue.Type;
-import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.ClientSmallScanner.SmallScannerCallableFactory;
import org.apache.hadoop.hbase.client.metrics.ScanMetrics;
import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
@@ -46,6 +32,16 @@ import org.mockito.Mockito;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Iterator;
+import java.util.Queue;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
/**
* Test the ClientSmallReversedScanner.
*/
@@ -178,7 +174,7 @@ public class TestClientSmallReversedScanner {
csrs.loadCache();
- List<Result> results = csrs.cache;
+ Queue<Result> results = csrs.cache;
Iterator<Result> iter = results.iterator();
assertEquals(3, results.size());
for (int i = 3; i >= 1 && iter.hasNext(); i--) {
@@ -248,7 +244,7 @@ public class TestClientSmallReversedScanner {
csrs.loadCache();
- List<Result> results = csrs.cache;
+ Queue<Result> results = csrs.cache;
Iterator<Result> iter = results.iterator();
assertEquals(2, results.size());
for (int i = 3; i >= 2 && iter.hasNext(); i--) {
@@ -264,7 +260,7 @@ public class TestClientSmallReversedScanner {
csrs.loadCache();
assertEquals(1, results.size());
- Result result = results.get(0);
+ Result result = results.peek();
assertEquals("row1", new String(result.getRow(), StandardCharsets.UTF_8));
assertEquals(1, result.getMap().size());
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallScanner.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallScanner.java b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallScanner.java
index 90bf4bb..318fbe7 100644
--- a/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallScanner.java
+++ b/hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientSmallScanner.java
@@ -17,22 +17,9 @@
*/
package org.apache.hadoop.hbase.client;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
-import java.io.IOException;
-import java.nio.charset.StandardCharsets;
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-
import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.HRegionInfo;
-import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.KeyValue.Type;
-import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.ClientSmallScanner.SmallScannerCallableFactory;
import org.apache.hadoop.hbase.client.metrics.ScanMetrics;
import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
@@ -45,6 +32,15 @@ import org.mockito.Mockito;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Queue;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
/**
* Test the ClientSmallScanner.
*/
@@ -176,10 +172,10 @@ public class TestClientSmallScanner {
css.loadCache();
- List<Result> results = css.cache;
+ Queue<Result> results = css.cache;
assertEquals(3, results.size());
for (int i = 1; i <= 3; i++) {
- Result result = results.get(i - 1);
+ Result result = results.poll();
byte[] row = result.getRow();
assertEquals("row" + i, new String(row, StandardCharsets.UTF_8));
assertEquals(1, result.getMap().size());
@@ -243,10 +239,10 @@ public class TestClientSmallScanner {
css.loadCache();
- List<Result> results = css.cache;
+ Queue<Result> results = css.cache;
assertEquals(2, results.size());
for (int i = 1; i <= 2; i++) {
- Result result = results.get(i - 1);
+ Result result = results.poll();
byte[] row = result.getRow();
assertEquals("row" + i, new String(row, StandardCharsets.UTF_8));
assertEquals(1, result.getMap().size());
@@ -258,7 +254,7 @@ public class TestClientSmallScanner {
css.loadCache();
assertEquals(1, results.size());
- Result result = results.get(0);
+ Result result = results.peek();
assertEquals("row3", new String(result.getRow(), StandardCharsets.UTF_8));
assertEquals(1, result.getMap().size());
assertTrue(css.closed);
http://git-wip-us.apache.org/repos/asf/hbase/blob/86b91997/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannersFromClientSide.java
----------------------------------------------------------------------
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannersFromClientSide.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannersFromClientSide.java
index fc04bf0..5afc226 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannersFromClientSide.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestScannersFromClientSide.java
@@ -642,6 +642,55 @@ public class TestScannersFromClientSide {
verifyResult(result, kvListExp, toLog, "Testing scan on re-opened region");
}
+ /**
+ * Test from client side for async scan
+ *
+ * @throws Exception
+ */
+ @Test
+ public void testAsyncScanner() throws Exception {
+ byte [] TABLE = Bytes.toBytes("testAsyncScan");
+ byte [][] ROWS = HTestConst.makeNAscii(ROW, 2);
+ byte [][] FAMILIES = HTestConst.makeNAscii(FAMILY, 3);
+ byte [][] QUALIFIERS = HTestConst.makeNAscii(QUALIFIER, 10);
+
+ HTable ht = TEST_UTIL.createTable(TABLE, FAMILIES);
+
+ Put put;
+ Scan scan;
+ Result result;
+ boolean toLog = true;
+ List<Cell> kvListExp, kvListScan;
+
+ kvListExp = new ArrayList<Cell>();
+
+ for (int r=0; r < ROWS.length; r++) {
+ put = new Put(ROWS[r]);
+ for (int c=0; c < FAMILIES.length; c++) {
+ for (int q=0; q < QUALIFIERS.length; q++) {
+ KeyValue kv = new KeyValue(ROWS[r], FAMILIES[c], QUALIFIERS[q], 1, VALUE);
+ put.add(kv);
+ kvListExp.add(kv);
+ }
+ }
+ ht.put(put);
+ }
+
+ scan = new Scan();
+ scan.setAsyncPrefetch(true);
+ ResultScanner scanner = ht.getScanner(scan);
+ kvListScan = new ArrayList<Cell>();
+ while ((result = scanner.next()) != null) {
+ for (Cell kv : result.listCells()) {
+ kvListScan.add(kv);
+ }
+ }
+ result = Result.create(kvListScan);
+ assertTrue("Not instance of async scanner",scanner instanceof ClientAsyncPrefetchScanner);
+ verifyResult(result, kvListExp, toLog, "Testing async scan");
+
+ }
+
static void verifyResult(Result result, List<Cell> expKvList, boolean toLog,
String msg) {