/*
* Copyright (C) 2012-2015 DataStax Inc.
*
* Licensed 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 com.datastax.driver.core;
import com.datastax.driver.core.utils.CassandraVersion;
import org.testng.annotations.Test;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import static org.testng.Assert.fail;
@CassandraVersion("2.1.0")
public class SingleConnectionPoolTest extends CCMTestsSupport {
@Test(groups = "short")
public void should_throttle_requests() {
// Throttle to a very low value. Even a single thread can generate a higher throughput.
final int maxRequests = 10;
cluster().getConfiguration().getPoolingOptions()
.setMaxRequestsPerConnection(HostDistance.LOCAL, maxRequests);
// Track in flight requests in a dedicated thread every second
final AtomicBoolean excessInflightQueriesSpotted = new AtomicBoolean(false);
final Host host = cluster().getMetadata().getHost(ccm().addressOfNode(1));
ScheduledExecutorService openConnectionsWatcherExecutor = Executors.newScheduledThreadPool(1);
final Runnable openConnectionsWatcher = new Runnable() {
@Override
public void run() {
int inFlight = session().getState().getInFlightQueries(host);
if (inFlight > maxRequests)
excessInflightQueriesSpotted.set(true);
}
};
openConnectionsWatcherExecutor.scheduleAtFixedRate(openConnectionsWatcher, 200, 200, TimeUnit.MILLISECONDS);
// Generate the load
for (int i = 0; i < 10000; i++)
session().executeAsync("SELECT release_version FROM system.local");
openConnectionsWatcherExecutor.shutdownNow();
if (excessInflightQueriesSpotted.get()) {
fail("Inflight queries exceeded the limit");
}
}
}