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* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.common.breaker;
import org.elasticsearch.common.settings.ImmutableSettings;
import org.elasticsearch.common.unit.ByteSizeValue;
import org.elasticsearch.indices.breaker.BreakerSettings;
import org.elasticsearch.indices.breaker.CircuitBreakerService;
import org.elasticsearch.indices.breaker.HierarchyCircuitBreakerService;
import org.elasticsearch.node.settings.NodeSettingsService;
import org.elasticsearch.test.ElasticsearchTestCase;
import org.junit.Test;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import static org.hamcrest.Matchers.equalTo;
/**
* Tests for the Memory Aggregating Circuit Breaker
*/
public class MemoryCircuitBreakerTests extends ElasticsearchTestCase {
@Test
public void testThreadedUpdatesToBreaker() throws Exception {
final int NUM_THREADS = scaledRandomIntBetween(3, 15);
final int BYTES_PER_THREAD = scaledRandomIntBetween(500, 4500);
final Thread[] threads = new Thread[NUM_THREADS];
final AtomicBoolean tripped = new AtomicBoolean(false);
final AtomicReference<Throwable> lastException = new AtomicReference<>(null);
final MemoryCircuitBreaker breaker = new MemoryCircuitBreaker(new ByteSizeValue((BYTES_PER_THREAD * NUM_THREADS) - 1), 1.0, logger);
for (int i = 0; i < NUM_THREADS; i++) {
threads[i] = new Thread(new Runnable() {
@Override
public void run() {
for (int j = 0; j < BYTES_PER_THREAD; j++) {
try {
breaker.addEstimateBytesAndMaybeBreak(1L, "test");
} catch (CircuitBreakingException e) {
if (tripped.get()) {
assertThat("tripped too many times", true, equalTo(false));
} else {
assertThat(tripped.compareAndSet(false, true), equalTo(true));
}
} catch (Throwable e2) {
lastException.set(e2);
}
}
}
});
threads[i].start();
}
for (Thread t : threads) {
t.join();
}
assertThat("no other exceptions were thrown", lastException.get(), equalTo(null));
assertThat("breaker was tripped exactly once", tripped.get(), equalTo(true));
assertThat("breaker was tripped exactly once", breaker.getTrippedCount(), equalTo(1L));
}
@Test
public void testThreadedUpdatesToChildBreaker() throws Exception {
final int NUM_THREADS = scaledRandomIntBetween(3, 15);
final int BYTES_PER_THREAD = scaledRandomIntBetween(500, 4500);
final Thread[] threads = new Thread[NUM_THREADS];
final AtomicBoolean tripped = new AtomicBoolean(false);
final AtomicReference<Throwable> lastException = new AtomicReference<>(null);
final AtomicReference<ChildMemoryCircuitBreaker> breakerRef = new AtomicReference<>(null);
final CircuitBreakerService service = new HierarchyCircuitBreakerService(ImmutableSettings.EMPTY, new NodeSettingsService(ImmutableSettings.EMPTY)) {
@Override
public CircuitBreaker getBreaker(CircuitBreaker.Name type) {
return breakerRef.get();
}
@Override
public void checkParentLimit(String label) throws CircuitBreakingException {
// never trip
}
};
final BreakerSettings settings = new BreakerSettings(CircuitBreaker.Name.REQUEST, (BYTES_PER_THREAD * NUM_THREADS) - 1, 1.0);
final ChildMemoryCircuitBreaker breaker = new ChildMemoryCircuitBreaker(settings, logger,
(HierarchyCircuitBreakerService)service, CircuitBreaker.Name.REQUEST);
breakerRef.set(breaker);
for (int i = 0; i < NUM_THREADS; i++) {
threads[i] = new Thread(new Runnable() {
@Override
public void run() {
for (int j = 0; j < BYTES_PER_THREAD; j++) {
try {
breaker.addEstimateBytesAndMaybeBreak(1L, "test");
} catch (CircuitBreakingException e) {
if (tripped.get()) {
assertThat("tripped too many times", true, equalTo(false));
} else {
assertThat(tripped.compareAndSet(false, true), equalTo(true));
}
} catch (Throwable e2) {
lastException.set(e2);
}
}
}
});
threads[i].start();
}
for (Thread t : threads) {
t.join();
}
assertThat("no other exceptions were thrown", lastException.get(), equalTo(null));
assertThat("breaker was tripped exactly once", tripped.get(), equalTo(true));
assertThat("breaker was tripped exactly once", breaker.getTrippedCount(), equalTo(1L));
}
@Test
public void testThreadedUpdatesToChildBreakerWithParentLimit() throws Exception {
final int NUM_THREADS = scaledRandomIntBetween(3, 15);
final int BYTES_PER_THREAD = scaledRandomIntBetween(500, 4500);
final int parentLimit = (BYTES_PER_THREAD * NUM_THREADS) - 2;
final int childLimit = parentLimit + 10;
final Thread[] threads = new Thread[NUM_THREADS];
final AtomicInteger tripped = new AtomicInteger(0);
final AtomicReference<Throwable> lastException = new AtomicReference<>(null);
final AtomicInteger parentTripped = new AtomicInteger(0);
final AtomicReference<ChildMemoryCircuitBreaker> breakerRef = new AtomicReference<>(null);
final CircuitBreakerService service = new HierarchyCircuitBreakerService(ImmutableSettings.EMPTY, new NodeSettingsService(ImmutableSettings.EMPTY)) {
@Override
public CircuitBreaker getBreaker(CircuitBreaker.Name type) {
return breakerRef.get();
}
@Override
public void checkParentLimit(String label) throws CircuitBreakingException {
// Parent will trip right before regular breaker would trip
if (getBreaker(CircuitBreaker.Name.REQUEST).getUsed() > parentLimit) {
parentTripped.incrementAndGet();
logger.info("--> parent tripped");
throw new CircuitBreakingException("parent tripped");
}
}
};
final BreakerSettings settings = new BreakerSettings(CircuitBreaker.Name.REQUEST, childLimit, 1.0);
final ChildMemoryCircuitBreaker breaker = new ChildMemoryCircuitBreaker(settings, logger,
(HierarchyCircuitBreakerService)service, CircuitBreaker.Name.REQUEST);
breakerRef.set(breaker);
for (int i = 0; i < NUM_THREADS; i++) {
threads[i] = new Thread(new Runnable() {
@Override
public void run() {
for (int j = 0; j < BYTES_PER_THREAD; j++) {
try {
breaker.addEstimateBytesAndMaybeBreak(1L, "test");
} catch (CircuitBreakingException e) {
tripped.incrementAndGet();
if (tripped.get() > 2) {
assertThat("tripped too many times: " + tripped.get(), true, equalTo(false));
}
} catch (Throwable e2) {
lastException.set(e2);
}
}
}
});
}
logger.info("--> NUM_THREADS: [{}], BYTES_PER_THREAD: [{}], TOTAL_BYTES: [{}], PARENT_LIMIT: [{}], CHILD_LIMIT: [{}]",
NUM_THREADS, BYTES_PER_THREAD, (BYTES_PER_THREAD * NUM_THREADS), parentLimit, childLimit);
logger.info("--> starting threads...");
for (Thread t : threads) {
t.start();
}
for (Thread t : threads) {
t.join();
}
logger.info("--> child breaker: used: {}, limit: {}", breaker.getUsed(), breaker.getLimit());
logger.info("--> parent tripped: {}, total trip count: {} (expecting 2 for each)", parentTripped.get(), tripped.get());
assertThat("no other exceptions were thrown", lastException.get(), equalTo(null));
assertThat("breaker should be reset back to the parent limit after parent breaker trips",
breaker.getUsed(), equalTo((long)parentLimit));
assertThat("parent breaker was tripped exactly twice", parentTripped.get(), equalTo(2));
assertThat("total breaker was tripped exactly twice", tripped.get(), equalTo(2));
assertThat("breaker total is expected value: " + parentLimit, breaker.getUsed(), equalTo((long)
parentLimit));
}
@Test
public void testConstantFactor() throws Exception {
final MemoryCircuitBreaker breaker = new MemoryCircuitBreaker(new ByteSizeValue(15), 1.6, logger);
String field = "myfield";
// add only 7 bytes
breaker.addWithoutBreaking(7);
try {
// this won't actually add it because it trips the breaker
breaker.addEstimateBytesAndMaybeBreak(3, field);
fail("should never reach this");
} catch (CircuitBreakingException cbe) {
}
// shouldn't throw an exception
breaker.addEstimateBytesAndMaybeBreak(2, field);
assertThat(breaker.getUsed(), equalTo(9L));
// adding 3 more bytes (now at 12)
breaker.addWithoutBreaking(3);
try {
// Adding no bytes still breaks
breaker.addEstimateBytesAndMaybeBreak(0, field);
fail("should never reach this");
} catch (CircuitBreakingException cbe) {
assertThat("breaker was tripped exactly twice", breaker.getTrippedCount(), equalTo(2L));
assertThat(cbe.getMessage().contains("field [" + field + "]"), equalTo(true));
}
}
}