Fix unresponsive network simulation (#42579)

Unresponsive network simulation would throw away requests. However, then
we no longer have any guarantees that a transport action either succeeds
or fails, which could lead to hangs (example: unclosed IndexShard
permits).

Closes #42244
This commit is contained in:
Henning Andersen 2019-06-11 17:40:40 +02:00 committed by Henning Andersen
parent d3136f99e6
commit 6108899a2d
2 changed files with 109 additions and 2 deletions

View File

@ -41,6 +41,7 @@ import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.common.util.MockPageCacheRecycler;
import org.elasticsearch.common.util.concurrent.AbstractRunnable;
import org.elasticsearch.common.util.concurrent.RunOnce;
import org.elasticsearch.core.internal.io.IOUtils;
import org.elasticsearch.indices.breaker.NoneCircuitBreakerService;
import org.elasticsearch.node.Node;
import org.elasticsearch.plugins.Plugin;
@ -68,6 +69,7 @@ import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.LinkedBlockingDeque;
@ -281,8 +283,25 @@ public final class MockTransportService extends TransportService {
return () -> {};
});
transport().addSendBehavior(transportAddress, (connection, requestId, action, request, options) -> {
transport().addSendBehavior(transportAddress, new StubbableTransport.SendRequestBehavior() {
private Set<Transport.Connection> toClose = ConcurrentHashMap.newKeySet();
@Override
public void sendRequest(Transport.Connection connection, long requestId, String action,
TransportRequest request, TransportRequestOptions options) {
// don't send anything, the receiving node is unresponsive
toClose.add(connection);
}
@Override
public void clearCallback() {
// close to simulate that tcp-ip eventually times out and closes connection (necessary to ensure transport eventually
// responds).
try {
IOUtils.close(toClose);
} catch (IOException e) {
throw new RuntimeException(e);
}
}
});
}

View File

@ -19,21 +19,33 @@
package org.elasticsearch.test.disruption;
import org.elasticsearch.action.admin.cluster.health.ClusterHealthAction;
import org.elasticsearch.action.admin.cluster.health.ClusterHealthRequest;
import org.elasticsearch.action.admin.cluster.health.ClusterHealthResponse;
import org.elasticsearch.cluster.NodeConnectionsService;
import org.elasticsearch.common.collect.Tuple;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.plugins.Plugin;
import org.elasticsearch.test.ESIntegTestCase;
import org.elasticsearch.test.InternalTestCluster;
import org.elasticsearch.test.disruption.NetworkDisruption.TwoPartitions;
import org.elasticsearch.test.transport.MockTransportService;
import org.elasticsearch.threadpool.ThreadPool;
import org.elasticsearch.transport.TransportException;
import org.elasticsearch.transport.TransportResponse;
import org.elasticsearch.transport.TransportResponseHandler;
import org.elasticsearch.transport.TransportService;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import static org.hamcrest.Matchers.greaterThanOrEqualTo;
@ -102,4 +114,80 @@ public class NetworkDisruptionIT extends ESIntegTestCase {
}
}
public void testTransportRespondsEventually() throws InterruptedException {
internalCluster().setBootstrapMasterNodeIndex(0);
internalCluster().ensureAtLeastNumDataNodes(randomIntBetween(3, 5));
final NetworkDisruption.DisruptedLinks disruptedLinks;
if (randomBoolean()) {
disruptedLinks = TwoPartitions.random(random(), internalCluster().getNodeNames());
} else {
disruptedLinks = NetworkDisruption.Bridge.random(random(), internalCluster().getNodeNames());
}
NetworkDisruption networkDisruption = new NetworkDisruption(disruptedLinks, randomFrom(new NetworkDisruption.NetworkUnresponsive(),
new NetworkDisruption.NetworkDisconnect(), NetworkDisruption.NetworkDelay.random(random())));
internalCluster().setDisruptionScheme(networkDisruption);
networkDisruption.startDisrupting();
int requests = randomIntBetween(1, 200);
CountDownLatch latch = new CountDownLatch(requests);
for (int i = 0; i < requests - 1; ++i) {
sendRequest(
internalCluster().getInstance(TransportService.class), internalCluster().getInstance(TransportService.class),
latch);
}
// send a request that is guaranteed disrupted.
Tuple<TransportService, TransportService> disruptedPair = findDisruptedPair(disruptedLinks);
sendRequest(disruptedPair.v1(), disruptedPair.v2(), latch);
// give a bit of time to send something under disruption.
assertFalse(latch.await(500, TimeUnit.MILLISECONDS)
&& networkDisruption.getNetworkLinkDisruptionType() instanceof NetworkDisruption.NetworkDisconnect == false);
networkDisruption.stopDisrupting();
latch.await(30, TimeUnit.SECONDS);
assertEquals("All requests must respond, requests: " + requests, 0, latch.getCount());
}
private Tuple<TransportService, TransportService> findDisruptedPair(NetworkDisruption.DisruptedLinks disruptedLinks) {
Optional<Tuple<TransportService, TransportService>> disruptedPair = disruptedLinks.nodes().stream()
.flatMap(n1 -> disruptedLinks.nodes().stream().map(n2 -> Tuple.tuple(n1, n2)))
.filter(pair -> disruptedLinks.disrupt(pair.v1(), pair.v2()))
.map(pair -> Tuple.tuple(internalCluster().getInstance(TransportService.class, pair.v1()),
internalCluster().getInstance(TransportService.class, pair.v2())))
.findFirst();
// since we have 3+ nodes, we are sure to find a disrupted pair, also for bridge disruptions.
assertTrue(disruptedPair.isPresent());
return disruptedPair.get();
}
private void sendRequest(TransportService source, TransportService target, CountDownLatch latch) {
source.sendRequest(target.getLocalNode(), ClusterHealthAction.NAME, new ClusterHealthRequest(),
new TransportResponseHandler<TransportResponse>() {
private AtomicBoolean responded = new AtomicBoolean();
@Override
public void handleResponse(TransportResponse response) {
assertTrue(responded.compareAndSet(false, true));
latch.countDown();
}
@Override
public void handleException(TransportException exp) {
assertTrue(responded.compareAndSet(false, true));
latch.countDown();
}
@Override
public String executor() {
return ThreadPool.Names.SAME;
}
@Override
public TransportResponse read(StreamInput in) throws IOException {
return ClusterHealthResponse.readResponseFrom(in);
}
});
}
}