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in repository https://gitbox.apache.org/repos/asf/servicecomb-java-chassis.git
The following commit(s) were added to refs/heads/master by this push:
new 5afdf71 [SCB-2077] fix instance isolation trying chance not released
problem (#1936)
5afdf71 is described below
commit 5afdf71abc27011340190dcc7d0c2d6056ecfb15
Author: yhs0092 <[email protected]>
AuthorDate: Tue Sep 8 08:54:12 2020 +0800
[SCB-2077] fix instance isolation trying chance not released problem (#1936)
---
.../servicecomb/loadbalance/Configuration.java | 16 ++++++
.../loadbalance/LoadbalanceHandler.java | 5 +-
.../loadbalance/ServiceCombServerStats.java | 41 +++++++++++-----
.../loadbalance/TryingIsolatedServerMarker.java | 56 +++++++++++++++++++++
.../filter/IsolationDiscoveryFilter.java | 8 +--
.../servicecomb/loadbalance/TestConfiguration.java | 18 ++++++-
.../loadbalance/TestLoadBalanceHandler2.java | 8 +--
.../loadbalance/TestServiceCombServerStats.java | 57 ++++++++++++++++++++++
.../filter/IsolationDiscoveryFilterTest.java | 14 +++---
9 files changed, 187 insertions(+), 36 deletions(-)
diff --git
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/Configuration.java
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/Configuration.java
index 60ab434..6ff3539 100644
---
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/Configuration.java
+++
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/Configuration.java
@@ -66,6 +66,8 @@ public final class Configuration {
public static final String FILTER_SINGLE_TEST = "singleTestTime";
+ public static final String FILTER_MAX_SINGLE_TEST_WINDOW =
"maxSingleTestWindow";
+
public static final String FILTER_MIN_ISOLATION_TIME = "minIsolationTime";
public static final String FILTER_CONTINUOUS_FAILURE_THRESHOLD =
"continuousFailureThreshold";
@@ -183,7 +185,21 @@ public final class Configuration {
return result;
}
return defaultValue;
+ } catch (NumberFormatException e) {
+ return defaultValue;
+ }
+ }
+ public int getMaxSingleTestWindow() {
+ final int defaultValue = 60000;
+ String p = getStringProperty(Integer.toString(defaultValue),
+ ROOT + FILTER_ISOLATION + FILTER_MAX_SINGLE_TEST_WINDOW);
+ try {
+ int result = Integer.parseInt(p);
+ if (result >= 0) {
+ return result;
+ }
+ return defaultValue;
} catch (NumberFormatException e) {
return defaultValue;
}
diff --git
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/LoadbalanceHandler.java
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/LoadbalanceHandler.java
index a539f90..8f7a524 100644
---
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/LoadbalanceHandler.java
+++
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/LoadbalanceHandler.java
@@ -40,7 +40,6 @@ import
org.apache.servicecomb.core.provider.consumer.SyncResponseExecutor;
import org.apache.servicecomb.foundation.common.cache.VersionedCache;
import org.apache.servicecomb.foundation.common.concurrent.ConcurrentHashMapEx;
import org.apache.servicecomb.foundation.common.utils.ExceptionUtils;
-import org.apache.servicecomb.loadbalance.filter.IsolationDiscoveryFilter;
import org.apache.servicecomb.loadbalance.filter.ServerDiscoveryFilter;
import org.apache.servicecomb.registry.discovery.DiscoveryContext;
import org.apache.servicecomb.registry.discovery.DiscoveryFilter;
@@ -196,9 +195,7 @@ public class LoadbalanceHandler implements Handler {
public void handle(Invocation invocation, AsyncResponse asyncResp) throws
Exception {
AsyncResponse response = asyncResp;
asyncResp = async -> {
- if
(Boolean.TRUE.equals(invocation.getLocalContext(IsolationDiscoveryFilter.TRYING_INSTANCES_EXISTING)))
{
- ServiceCombServerStats.releaseTryingChance();
- }
+ ServiceCombServerStats.checkAndReleaseTryingChance(invocation);
response.handle(async);
};
diff --git
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/ServiceCombServerStats.java
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/ServiceCombServerStats.java
index daf83dc..6afc0f6 100644
---
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/ServiceCombServerStats.java
+++
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/ServiceCombServerStats.java
@@ -18,9 +18,10 @@
package org.apache.servicecomb.loadbalance;
import java.time.Clock;
-import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.atomic.AtomicReference;
+import org.apache.servicecomb.core.Invocation;
import org.apache.servicecomb.foundation.common.utils.TimeUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@@ -35,15 +36,14 @@ public class ServiceCombServerStats {
private static final Logger LOGGER =
LoggerFactory.getLogger(ServiceCombServerStats.class);
+ private final Object lock = new Object();
+
/**
* There is not more than 1 server allowed to stay in TRYING status
concurrently.
- * If the value of globalAllowIsolatedServerTryingFlag is false, there have
been 1 server in
- * TRYING status, so the other isolated servers cannot be transferred into
- * TRYING status; otherwise the value of globalAllowIsolatedServerTryingFlag
is true.
+ * This flag is designed to ensure such mechanism. And it makes the
ServiceCombServerStats stateful.
+ * Therefore, the flag should be reset correctly after the trying server
gets handled.
*/
- private static AtomicBoolean globalAllowIsolatedServerTryingFlag = new
AtomicBoolean(true);
-
- private final Object lock = new Object();
+ static AtomicReference<TryingIsolatedServerMarker>
globalAllowIsolatedServerTryingFlag = new AtomicReference<>();
Clock clock;
@@ -73,7 +73,7 @@ public class ServiceCombServerStats {
init();
}
- private void init(){
+ private void init() {
lastWindow = clock.millis();
continuousFailureCount = new AtomicLong(0);
lastVisitTime = clock.millis();
@@ -84,7 +84,11 @@ public class ServiceCombServerStats {
}
public static boolean isolatedServerCanTry() {
- return globalAllowIsolatedServerTryingFlag.get();
+ TryingIsolatedServerMarker marker =
globalAllowIsolatedServerTryingFlag.get();
+ if (marker == null) {
+ return true;
+ }
+ return marker.isOutdated();
}
/**
@@ -92,12 +96,23 @@ public class ServiceCombServerStats {
*
* @return true if the chance is applied successfully, otherwise false
*/
- public static boolean applyForTryingChance() {
- return isolatedServerCanTry() &&
globalAllowIsolatedServerTryingFlag.compareAndSet(true, false);
+ public static boolean applyForTryingChance(Invocation invocation) {
+ TryingIsolatedServerMarker marker =
globalAllowIsolatedServerTryingFlag.get();
+ if (marker == null) {
+ return globalAllowIsolatedServerTryingFlag.compareAndSet(null, new
TryingIsolatedServerMarker(invocation));
+ }
+ if (marker.isOutdated()) {
+ return globalAllowIsolatedServerTryingFlag.compareAndSet(marker, new
TryingIsolatedServerMarker(invocation));
+ }
+ return false;
}
- public static void releaseTryingChance() {
- globalAllowIsolatedServerTryingFlag.set(true);
+ public static void checkAndReleaseTryingChance(Invocation invocation) {
+ TryingIsolatedServerMarker marker =
globalAllowIsolatedServerTryingFlag.get();
+ if (marker == null || marker.getInvocation() != invocation) {
+ return;
+ }
+ globalAllowIsolatedServerTryingFlag.compareAndSet(marker, null);
}
public void markIsolated(boolean isolated) {
diff --git
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/TryingIsolatedServerMarker.java
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/TryingIsolatedServerMarker.java
new file mode 100644
index 0000000..a741a8d
--- /dev/null
+++
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/TryingIsolatedServerMarker.java
@@ -0,0 +1,56 @@
+/*
+ * 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.servicecomb.loadbalance;
+
+import java.time.Clock;
+import java.util.Objects;
+
+import org.apache.servicecomb.core.Invocation;
+import org.apache.servicecomb.foundation.common.utils.TimeUtils;
+
+public class TryingIsolatedServerMarker {
+ Clock clock;
+
+ final long startTryingTimestamp;
+
+ private final Invocation invocation;
+
+ /**
+ * To make sure even if some error interrupted the releasing operation of
+ * {@link ServiceCombServerStats#globalAllowIsolatedServerTryingFlag},
+ * the state can still be recovered.
+ */
+ private final int maxSingleTestWindow;
+
+ public TryingIsolatedServerMarker(Invocation invocation) {
+ Objects.requireNonNull(invocation, "invocation should be non-null");
+ this.invocation = invocation;
+ clock = TimeUtils.getSystemDefaultZoneClock();
+ startTryingTimestamp = clock.millis();
+ maxSingleTestWindow = Configuration.INSTANCE.getMaxSingleTestWindow();
+ }
+
+ public boolean isOutdated() {
+ return this.invocation.isFinished()
+ || clock.millis() - startTryingTimestamp >= maxSingleTestWindow;
+ }
+
+ public Invocation getInvocation() {
+ return invocation;
+ }
+}
diff --git
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilter.java
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilter.java
index c8f4289..46dec17 100644
---
a/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilter.java
+++
b/handlers/handler-loadbalance/src/main/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilter.java
@@ -144,13 +144,7 @@ public class IsolationDiscoveryFilter implements
DiscoveryFilter {
if (!checkThresholdAllowed(settings, serverStats)) {
if (serverStats.isIsolated()
&& (System.currentTimeMillis() - serverStats.getLastVisitTime()) >
settings.singleTestTime) {
- if (!ServiceCombServerStats.applyForTryingChance()) {
- // this server hasn't been isolated for enough long time, or there
is no trying chance
- return false;
- }
- // [1]we can implement better recovery based on several attempts, but
here we do not know if this attempt is success
- invocation.addLocalContext(TRYING_INSTANCES_EXISTING, Boolean.TRUE);
- return true;
+ return ServiceCombServerStats.applyForTryingChance(invocation);
}
if (!serverStats.isIsolated()) {
serverStats.markIsolated(true);
diff --git
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestConfiguration.java
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestConfiguration.java
index 862e2dc..2dfaa52 100644
---
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestConfiguration.java
+++
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestConfiguration.java
@@ -21,10 +21,13 @@ import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
-import com.netflix.config.ConcurrentCompositeConfiguration;
import org.apache.servicecomb.config.ConfigUtil;
+import org.apache.servicecomb.foundation.test.scaffolding.config.ArchaiusUtils;
+import org.junit.After;
import org.junit.Test;
+import com.netflix.config.ConcurrentCompositeConfiguration;
+
import mockit.Mock;
import mockit.MockUp;
@@ -32,6 +35,10 @@ import mockit.MockUp;
*
*/
public class TestConfiguration {
+ @After
+ public void after() {
+ ArchaiusUtils.resetConfig();
+ }
@Test
public void testConstants() {
@@ -42,6 +49,7 @@ public class TestConfiguration {
assertEquals("retryOnNext", Configuration.RETRY_ON_NEXT);
assertEquals("retryOnSame", Configuration.RETRY_ON_SAME);
assertEquals("SessionStickinessRule.successiveFailedTimes",
Configuration.SUCCESSIVE_FAILED_TIMES);
+ assertEquals("maxSingleTestWindow",
Configuration.FILTER_MAX_SINGLE_TEST_WINDOW);
assertNotNull(Configuration.INSTANCE);
}
@@ -173,4 +181,12 @@ public class TestConfiguration {
localConfiguration = ConfigUtil.createLocalConfig();
assertEquals("100",
localConfiguration.getProperty(Configuration.TIMER_INTERVAL_IN_MILLIS));
}
+
+ @Test
+ public void testGetMaxSingleTestWindow() {
+ assertEquals(60000, Configuration.INSTANCE.getMaxSingleTestWindow());
+
+
ArchaiusUtils.setProperty("servicecomb.loadbalance.isolation.maxSingleTestWindow",
5000);
+ assertEquals(5000, Configuration.INSTANCE.getMaxSingleTestWindow());
+ }
}
diff --git
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestLoadBalanceHandler2.java
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestLoadBalanceHandler2.java
index 0ff8852..13e57ba 100644
---
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestLoadBalanceHandler2.java
+++
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestLoadBalanceHandler2.java
@@ -94,7 +94,7 @@ public class TestLoadBalanceHandler2 {
// avoid mock
ServiceCombLoadBalancerStats.INSTANCE.init();
- ServiceCombServerStats.releaseTryingChance();
+ TestServiceCombServerStats.releaseTryingChance();
mockTimeMillis = new Holder<>(1L);
new MockUp<System>() {
@@ -107,7 +107,7 @@ public class TestLoadBalanceHandler2 {
@After
public void teardown() {
- ServiceCombServerStats.releaseTryingChance();
+ TestServiceCombServerStats.releaseTryingChance();
}
@Test
@@ -866,7 +866,7 @@ public class TestLoadBalanceHandler2 {
aysnc.success("OK");
});
- Assert.assertTrue(ServiceCombServerStats.applyForTryingChance());
+ Assert.assertTrue(ServiceCombServerStats.applyForTryingChance(invocation));
invocation.addLocalContext(IsolationDiscoveryFilter.TRYING_INSTANCES_EXISTING,
true);
try {
handler.handle(invocation, (response) -> Assert.assertEquals("OK",
response.getResult()));
@@ -923,7 +923,7 @@ public class TestLoadBalanceHandler2 {
}
});
- Assert.assertTrue(ServiceCombServerStats.applyForTryingChance());
+ Assert.assertTrue(ServiceCombServerStats.applyForTryingChance(invocation));
invocation.addLocalContext(IsolationDiscoveryFilter.TRYING_INSTANCES_EXISTING,
true);
try {
handler.handle(invocation, (response) -> Assert.assertEquals("OK",
response.getResult()));
diff --git
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestServiceCombServerStats.java
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestServiceCombServerStats.java
index 9fd3aaf..2ea105a 100644
---
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestServiceCombServerStats.java
+++
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/TestServiceCombServerStats.java
@@ -17,15 +17,29 @@
package org.apache.servicecomb.loadbalance;
+import java.util.Optional;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
+import org.apache.servicecomb.core.Invocation;
import org.apache.servicecomb.foundation.common.Holder;
import org.apache.servicecomb.foundation.common.testing.MockClock;
+import org.junit.After;
import org.junit.Assert;
+import org.junit.Before;
import org.junit.Test;
public class TestServiceCombServerStats {
+ @Before
+ public void before() {
+ releaseTryingChance();
+ }
+
+ @After
+ public void after() {
+ releaseTryingChance();
+ }
+
@Test
public void testSimpleThread() {
long time = System.currentTimeMillis();
@@ -80,4 +94,47 @@ public class TestServiceCombServerStats {
Assert.assertEquals(0, stats.getFailedRate());
Assert.assertEquals(100, stats.getSuccessRate());
}
+
+ @Test
+ public void
testGlobalAllowIsolatedServerTryingFlag_apply_with_null_precondition() {
+ Invocation invocation = new Invocation();
+ Assert.assertTrue(ServiceCombServerStats.applyForTryingChance(invocation));
+ Assert.assertSame(invocation,
ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().getInvocation());
+ }
+
+ @Test
+ public void
testGlobalAllowIsolatedServerTryingFlag_apply_with_chance_occupied() {
+ Invocation invocation = new Invocation();
+ Assert.assertTrue(ServiceCombServerStats.applyForTryingChance(invocation));
+ Assert.assertSame(invocation,
ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().getInvocation());
+
+ Invocation otherInvocation = new Invocation();
+
Assert.assertFalse(ServiceCombServerStats.applyForTryingChance(otherInvocation));
+ Assert.assertSame(invocation,
ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().getInvocation());
+ }
+
+ @Test
+ public void
testGlobalAllowIsolatedServerTryingFlag_apply_with_flag_outdated() {
+ Invocation invocation = new Invocation();
+ Assert.assertTrue(ServiceCombServerStats.applyForTryingChance(invocation));
+ Assert.assertSame(invocation,
ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().getInvocation());
+ ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().clock =
new MockClock(new Holder<>(
+
ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().startTryingTimestamp
+ 60000
+ ));
+
+ Invocation otherInvocation = new Invocation();
+
Assert.assertTrue(ServiceCombServerStats.applyForTryingChance(otherInvocation));
+ Assert
+ .assertSame(otherInvocation,
ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get().getInvocation());
+ }
+
+ public static void releaseTryingChance() {
+ ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.set(null);
+ }
+
+ public static Invocation getTryingIsolatedServerInvocation() {
+ return
Optional.ofNullable(ServiceCombServerStats.globalAllowIsolatedServerTryingFlag.get())
+ .map(TryingIsolatedServerMarker::getInvocation)
+ .orElse(null);
+ }
}
diff --git
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilterTest.java
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilterTest.java
index d1d0467..1728161 100644
---
a/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilterTest.java
+++
b/handlers/handler-loadbalance/src/test/java/org/apache/servicecomb/loadbalance/filter/IsolationDiscoveryFilterTest.java
@@ -27,6 +27,7 @@ import org.apache.servicecomb.loadbalance.Configuration;
import org.apache.servicecomb.loadbalance.ServiceCombLoadBalancerStats;
import org.apache.servicecomb.loadbalance.ServiceCombServer;
import org.apache.servicecomb.loadbalance.ServiceCombServerStats;
+import org.apache.servicecomb.loadbalance.TestServiceCombServerStats;
import org.apache.servicecomb.registry.api.registry.MicroserviceInstance;
import org.apache.servicecomb.registry.cache.CacheEndpoint;
import org.apache.servicecomb.registry.discovery.DiscoveryContext;
@@ -80,13 +81,13 @@ public class IsolationDiscoveryFilterTest {
discoveryTreeNode.data(data);
filter = new IsolationDiscoveryFilter();
- ServiceCombServerStats.releaseTryingChance();
+ TestServiceCombServerStats.releaseTryingChance();
}
@After
public void after() {
Deencapsulation.invoke(ServiceCombLoadBalancerStats.INSTANCE, "init");
- ServiceCombServerStats.releaseTryingChance();
+ TestServiceCombServerStats.releaseTryingChance();
}
@Test
@@ -137,8 +138,7 @@ public class IsolationDiscoveryFilterTest {
ServiceCombLoadBalancerStats.INSTANCE.markIsolated(server0, true);
Assert.assertTrue(ServiceCombServerStats.isolatedServerCanTry());
- Assert.assertFalse(
-
Boolean.TRUE.equals(invocation.getLocalContext(IsolationDiscoveryFilter.TRYING_INSTANCES_EXISTING)));
+
Assert.assertNull(TestServiceCombServerStats.getTryingIsolatedServerInvocation());
DiscoveryTreeNode childNode = filter.discovery(discoveryContext,
discoveryTreeNode);
Map<String, MicroserviceInstance> childNodeData = childNode.data();
Assert.assertThat(childNodeData.keySet(),
Matchers.containsInAnyOrder("i0", "i1", "i2"));
@@ -147,8 +147,7 @@ public class IsolationDiscoveryFilterTest {
Assert.assertEquals(data.get("i2"), childNodeData.get("i2"));
Assert.assertTrue(serviceCombServerStats.isIsolated());
Assert.assertFalse(ServiceCombServerStats.isolatedServerCanTry());
- Assert.assertTrue(
-
Boolean.TRUE.equals(invocation.getLocalContext(IsolationDiscoveryFilter.TRYING_INSTANCES_EXISTING)));
+ Assert.assertSame(invocation,
TestServiceCombServerStats.getTryingIsolatedServerInvocation());
}
@Test
@@ -180,7 +179,8 @@ public class IsolationDiscoveryFilterTest {
Assert.assertEquals(data.get("i1"), childNodeData.get("i1"));
Assert.assertEquals(data.get("i2"), childNodeData.get("i2"));
- ServiceCombServerStats.releaseTryingChance(); // after the first
invocation releases the trying chance
+ ServiceCombServerStats
+ .checkAndReleaseTryingChance(invocation); // after the first
invocation releases the trying chance
// Other invocation can get the trying chance
childNode = filter.discovery(discoveryContext, discoveryTreeNode);
