Profiling has shown that the cost of performing a forced context switch
in execution path of the data store leads to ~2x performance
degradation (23600 vs. 40000 ops/s), with average of 20 runs:
InMemoryDataStoreWithExecutorServiceBenchmark: total stddev
write100KSingleNodeWithOneInnerItemInCommitPerWriteBenchmark 4227.384 ms 61.172
write100KSingleNodeWithOneInnerItemInOneCommitBenchmark 286.954 ms 14.350
write10KSingleNodeWithTenInnerItemsInCommitPerWriteBenchmark 364.004 ms 12.687
write10KSingleNodeWithTenInnerItemsInOneCommitBenchmark 17.936 ms 0.883
write50KSingleNodeWithTwoInnerItemsInCommitPerWriteBenchmark 1979.140 ms 56.529
write50KSingleNodeWithTwoInnerItemsInOneCommitBenchmark 136.749 ms 6.402
InMemoryDataStoreWithSameThreadedExecutorBenchmark: total stddev
write100KSingleNodeWithOneInnerItemInCommitPerWriteBenchmark 2475.137 ms 220.396
write100KSingleNodeWithOneInnerItemInOneCommitBenchmark 267.298 ms 7.063
write10KSingleNodeWithTenInnerItemsInCommitPerWriteBenchmark 180.537 ms 1.337
write10KSingleNodeWithTenInnerItemsInOneCommitBenchmark 19.582 ms 0.200
write50KSingleNodeWithTwoInnerItemsInCommitPerWriteBenchmark 1127.771 ms 87.438
write50KSingleNodeWithTwoInnerItemsInOneCommitBenchmark 134.401 ms 2.110
The analysis is that the underlying component (yang-data-impl's
DataTree) can process operations at a rate exceeding 30K ops/s,
obviously depending on size, which means a transaction is completed
every ~35 microseconds. When we factor in the fact that there is at most
one transaction issued at a particular moment (due to ordering/conflict
resolution), the ill effects of forced context switches become very much
pronounced.
This patch switches the executor service to SameThreadExecutor, which
foregoes queueing and executes the task on the submitting thread (which
is the datastore coordinator thread, not some user thread).
The option to switch the executor service is left intact, but may be
removed in future pending further benchmarks.
Change-Id: Ic1c4c0b1b80aa77c2d85810736bdc370a465eee8
Signed-off-by: Robert Varga <rovarga@cisco.com>
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
-import com.google.common.util.concurrent.MoreExecutors;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;
private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
private final ListenerTree listenerTree = ListenerTree.create();
private final AtomicLong txCounter = new AtomicLong(0);
private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
private final ListenerTree listenerTree = ListenerTree.create();
private final AtomicLong txCounter = new AtomicLong(0);
- private final ListeningExecutorService listeningExecutor;
private final QueuedNotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
private final ExecutorService dataChangeListenerExecutor;
private final QueuedNotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
private final ExecutorService dataChangeListenerExecutor;
-
- private final ExecutorService domStoreExecutor;
+ private final ListeningExecutorService commitExecutor;
private final boolean debugTransactions;
private final String name;
private volatile AutoCloseable closeable;
private final boolean debugTransactions;
private final String name;
private volatile AutoCloseable closeable;
- public InMemoryDOMDataStore(final String name, final ExecutorService domStoreExecutor,
+ public InMemoryDOMDataStore(final String name, final ListeningExecutorService commitExecutor,
final ExecutorService dataChangeListenerExecutor) {
final ExecutorService dataChangeListenerExecutor) {
- this(name, domStoreExecutor, dataChangeListenerExecutor,
+ this(name, commitExecutor, dataChangeListenerExecutor,
InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE, false);
}
InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE, false);
}
- public InMemoryDOMDataStore(final String name, final ExecutorService domStoreExecutor,
+ public InMemoryDOMDataStore(final String name, final ListeningExecutorService commitExecutor,
final ExecutorService dataChangeListenerExecutor, final int maxDataChangeListenerQueueSize,
final boolean debugTransactions) {
this.name = Preconditions.checkNotNull(name);
final ExecutorService dataChangeListenerExecutor, final int maxDataChangeListenerQueueSize,
final boolean debugTransactions) {
this.name = Preconditions.checkNotNull(name);
- this.domStoreExecutor = Preconditions.checkNotNull(domStoreExecutor);
- this.listeningExecutor = MoreExecutors.listeningDecorator(this.domStoreExecutor);
+ this.commitExecutor = Preconditions.checkNotNull(commitExecutor);
this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
this.debugTransactions = debugTransactions;
this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
this.debugTransactions = debugTransactions;
}
public ExecutorService getDomStoreExecutor() {
}
public ExecutorService getDomStoreExecutor() {
- return domStoreExecutor;
@Override
public void close() {
@Override
public void close() {
- ExecutorServiceUtil.tryGracefulShutdown(listeningExecutor, 30, TimeUnit.SECONDS);
+ ExecutorServiceUtil.tryGracefulShutdown(commitExecutor, 30, TimeUnit.SECONDS);
ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
if(closeable != null) {
ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
if(closeable != null) {
@Override
public ListenableFuture<Boolean> canCommit() {
@Override
public ListenableFuture<Boolean> canCommit() {
- return listeningExecutor.submit(new Callable<Boolean>() {
+ return commitExecutor.submit(new Callable<Boolean>() {
@Override
public Boolean call() throws TransactionCommitFailedException {
try {
@Override
public Boolean call() throws TransactionCommitFailedException {
try {
@Override
public ListenableFuture<Void> preCommit() {
@Override
public ListenableFuture<Void> preCommit() {
- return listeningExecutor.submit(new Callable<Void>() {
+ return commitExecutor.submit(new Callable<Void>() {
@Override
public Void call() {
candidate = dataTree.prepare(modification);
@Override
public Void call() {
candidate = dataTree.prepare(modification);
*/
package org.opendaylight.controller.md.sal.dom.store.impl;
*/
package org.opendaylight.controller.md.sal.dom.store.impl;
+import com.google.common.util.concurrent.ListeningExecutorService;
+import com.google.common.util.concurrent.MoreExecutors;
import java.util.concurrent.ExecutorService;
import javax.annotation.Nullable;
import org.opendaylight.controller.sal.core.api.model.SchemaService;
import java.util.concurrent.ExecutorService;
import javax.annotation.Nullable;
import org.opendaylight.controller.sal.core.api.model.SchemaService;
@Nullable final InMemoryDOMDataStoreConfigProperties properties) {
InMemoryDOMDataStoreConfigProperties actualProperties = properties;
@Nullable final InMemoryDOMDataStoreConfigProperties properties) {
InMemoryDOMDataStoreConfigProperties actualProperties = properties;
- if(actualProperties == null) {
+ if (actualProperties == null) {
actualProperties = InMemoryDOMDataStoreConfigProperties.getDefault();
}
actualProperties = InMemoryDOMDataStoreConfigProperties.getDefault();
}
// task execution time to get higher throughput as DataChangeListeners typically provide
// much of the business logic for a data model. If the executor queue size limit is reached,
// subsequent submitted notifications will block the calling thread.
// task execution time to get higher throughput as DataChangeListeners typically provide
// much of the business logic for a data model. If the executor queue size limit is reached,
// subsequent submitted notifications will block the calling thread.
int dclExecutorMaxQueueSize = actualProperties.getMaxDataChangeExecutorQueueSize();
int dclExecutorMaxPoolSize = actualProperties.getMaxDataChangeExecutorPoolSize();
ExecutorService dataChangeListenerExecutor = SpecialExecutors.newBlockingBoundedFastThreadPool(
dclExecutorMaxPoolSize, dclExecutorMaxQueueSize, name + "-DCL" );
int dclExecutorMaxQueueSize = actualProperties.getMaxDataChangeExecutorQueueSize();
int dclExecutorMaxPoolSize = actualProperties.getMaxDataChangeExecutorPoolSize();
ExecutorService dataChangeListenerExecutor = SpecialExecutors.newBlockingBoundedFastThreadPool(
dclExecutorMaxPoolSize, dclExecutorMaxQueueSize, name + "-DCL" );
- ExecutorService domStoreExecutor = SpecialExecutors.newBoundedSingleThreadExecutor(
- actualProperties.getMaxDataStoreExecutorQueueSize(), "DOMStore-" + name );
-
- InMemoryDOMDataStore dataStore = new InMemoryDOMDataStore(name,
- domStoreExecutor, dataChangeListenerExecutor,
+ final ListeningExecutorService commitExecutor = MoreExecutors.sameThreadExecutor();
+ final InMemoryDOMDataStore dataStore = new InMemoryDOMDataStore(name,
+ commitExecutor, dataChangeListenerExecutor,
actualProperties.getMaxDataChangeListenerQueueSize(), debugTransactions);
actualProperties.getMaxDataChangeListenerQueueSize(), debugTransactions);
- if(schemaService != null) {
+ if (schemaService != null) {
schemaService.registerSchemaContextListener(dataStore);
}
schemaService.registerSchemaContextListener(dataStore);
}
Code Review / controller.git / commitdiff