我们正在开发一个基于OrientDB图表的系统（OrientDB 2.1.3）。在应用程序中，我们有一个瘦的pojo-＆gt;图形持久层，可以正常工作，但是当多个线程更新数据库时，我得到OConcurrentModificationException。
以下是一个示例场景：
OConcurrentModificationException被抛出顶点已更新。请注意，我并未尝试保存或修改Color＆＃34; Blue＆＃34;顶点本身。据我所知，http://orientdb.com/docs/2.1/Concurrency.html#concurrency-on-adding-edges设置-DridBag.embeddedToSbtreeBonsaiThreshold=-1的文档可以帮助我避免我的问题，尽管它仍然无效。
我错过了什么？我还能做些什么来避免这种情况吗？
更新：
例外的Stacktrace：
Error on releasing database 'infogileorientdatabasetest' in pool
com.orientechnologies.orient.core.exception.OConcurrentModificationException: Cannot UPDATE the record #40:1 because the version is not the latest. Probably you are updating an old record or it has been modified by another user (db=v34 your=v33)
at com.orientechnologies.orient.core.conflict.OVersionRecordConflictStrategy.checkVersions(OVersionRecordConflictStrategy.java:55)
at com.orientechnologies.orient.core.conflict.OVersionRecordConflictStrategy.onUpdate(OVersionRecordConflictStrategy.java:42)
at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.checkAndIncrementVersion(OAbstractPaginatedStorage.java:2279)
at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.doUpdateRecord(OAbstractPaginatedStorage.java:1911)
at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.commitEntry(OAbstractPaginatedStorage.java:2364)
at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.commit(OAbstractPaginatedStorage.java:1111)
at com.orientechnologies.orient.core.tx.OTransactionOptimistic.doCommit(OTransactionOptimistic.java:609)
at com.orientechnologies.orient.core.tx.OTransactionOptimistic.commit(OTransactionOptimistic.java:156)
at com.orientechnologies.orient.core.db.document.ODatabaseDocumentTx.commit(ODatabaseDocumentTx.java:2582)
at com.orientechnologies.orient.core.db.document.ODatabaseDocumentTx.commit(ODatabaseDocumentTx.java:2551)
at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.commit(ONetworkProtocolBinary.java:1221)
at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.executeRequest(ONetworkProtocolBinary.java:400)
at com.orientechnologies.orient.server.network.protocol.binary.OBinaryNetworkProtocolAbstract.execute(OBinaryNetworkProtocolAbstract.java:223)
at com.orientechnologies.common.thread.OSoftThread.run(OSoftThread.java:77)
更新2 - 测试用例 我使用此测试用例重现了错误。如果我做错了导致问题的话，我会很高兴...： - ）
更新3 在静态块中使用OGlobalConfiguration.RID_BAG_EMBEDDED_TO_SBTREEBONSAI_THRESHOLD.setValue(-1)更新了测试用例。
package se.infogile.persistence.orientdb;
import com.orientechnologies.orient.client.remote.OServerAdmin;
import com.orientechnologies.orient.core.config.OGlobalConfiguration;
import com.orientechnologies.orient.core.db.OPartitionedDatabasePool;
import com.orientechnologies.orient.core.db.OPartitionedDatabasePoolFactory;
import com.orientechnologies.orient.core.db.document.ODatabaseDocumentTx;
import com.orientechnologies.orient.core.exception.OConcurrentModificationException;
import com.orientechnologies.orient.core.exception.OConfigurationException;
import com.orientechnologies.orient.core.exception.OStorageException;
import com.orientechnologies.orient.core.tx.OTransaction;
import com.orientechnologies.orient.enterprise.channel.binary.OResponseProcessingException;
import com.orientechnologies.orient.server.OServer;
import com.orientechnologies.orient.server.OServerMain;
import com.orientechnologies.orient.server.config.OServerConfiguration;
import com.orientechnologies.orient.server.config.OServerConfigurationLoaderXml;
import com.orientechnologies.orient.server.config.OServerNetworkListenerConfiguration;
import com.tinkerpop.blueprints.Vertex;
import com.tinkerpop.blueprints.impls.orient.OrientGraph;
import org.apache.commons.io.FileUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.testng.Assert;
import org.testng.annotations.AfterSuite;
import org.testng.annotations.BeforeSuite;
import org.testng.annotations.Test;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.*;
/**
* Created by heintz on 14/10/15.
*/
public class OrientDBEdgeProblemTest {
static {
OGlobalConfiguration.RID_BAG_EMBEDDED_TO_SBTREEBONSAI_THRESHOLD.setValue(-1);
}
private static OPartitionedDatabasePoolFactory dbPoolFactory = new OPartitionedDatabasePoolFactory(100);
private static Logger logger = LoggerFactory.getLogger(OrientDBEdgeProblemTest.class);
private OServer server = null;
private static ExecutorService executorService = Executors.newFixedThreadPool(10);
private static final String dbName = "edgeproblemtest";
@Test
public void testVersionIncrementError() throws Throwable {
OrientGraph graph = getGraph(dbName);
graph.getRawGraph().setDefaultTransactionMode();
graph.createVertexType("Product");
graph.createVertexType("Color");
graph.createEdgeType("HasColor");
graph.getRawGraph().begin(OTransaction.TXTYPE.OPTIMISTIC);
// graph.begin();
Vertex v1 = graph.addVertex("Color", "name", "Blue");
graph.commit();
graph.shutdown();
char[] alphabet = new char[] {'A','B','C','D','E','F','G'};
List<Future> futures = new ArrayList<>();
for (int i = 0; i < 2; i++) {
int pos = i;
futures.add(executorService.submit(new Callable<Object>() {
@Override
public Object call() throws Exception {
OrientGraph g = getGraph(dbName);
try {
g.begin();
Vertex v2 = g.addVertex("Product", "name", "Product "+alphabet[pos]);
g.addEdge(null, v2, v1, "HasColor");
Thread.sleep(200);
g.commit();
} catch (OConcurrentModificationException ocme) {
logger.error("Exception while saving: ", ocme);
Assert.fail("OConcurrentModificationException");
} finally {
g.shutdown();
}
return null;
}
}));
}
for (Future f : futures) {
f.get();
}
executorService.shutdown();
executorService.awaitTermination(5, TimeUnit.SECONDS);
}
@AfterSuite
public void tearDown() throws Exception {
logger.info("Shutting down OrientDB");
if (server != null) {
server.shutdown();
}
}
private OrientGraph getGraph(String dbName) {
String _db = "remote:localhost:3424";
String url = _db + "/" + dbName;
ODatabaseDocumentTx db = null;
try {
OPartitionedDatabasePool pool = dbPoolFactory.get(url,
"root",
"admin");
db = pool.acquire();
} catch (OResponseProcessingException | OConfigurationException | OStorageException oce) {
try {
logger.info("creating new database named " + dbName);
System.err.println("Before DB creation");
OServerAdmin serverAdmin = new OServerAdmin(_db).connect(
"root",
"admin"
);
serverAdmin.createDatabase(dbName, "document", "plocal");
serverAdmin.close();
System.err.println("After DB creation");
} catch (IOException ex) {
logger.error("Unable to create database " + dbName, ex);
}
OPartitionedDatabasePool pool = dbPoolFactory.get(url,
"root",
"admin");
db = pool.acquire();
}
return new OrientGraph(db);
}
@BeforeSuite
public void setUpDatabase() throws Exception {
File f = new File(".");
InputStream is = GraphPersistenceServiceTest.class.getResourceAsStream("/orientdb.config");
Assert.assertNotNull(is);
logger.info("Starting OrientDB");
server = OServerMain.create();
OServerConfigurationLoaderXml loaderXml = new OServerConfigurationLoaderXml(OServerConfiguration.class, GraphPersistenceServiceTest.class.getResourceAsStream("/orientdb.config"));
OServerConfiguration oServerConfiguration = new OServerConfiguration(loaderXml);
System.setProperty("ORIENTDB_ROOT_PASSWORD", "admin");
System.setProperty("RUNMODE", "UNITTEST");
OServerNetworkListenerConfiguration networkConfig = oServerConfiguration.network.listeners.iterator().next();
networkConfig.portRange = "3424-3430";
server.setServerRootDirectory("./target/orientdb");
server.startup(oServerConfiguration);
File serverDir = new File("./target/orientdb");
if (serverDir.exists()) {
FileUtils.deleteDirectory(serverDir);
}
serverDir.mkdirs();
File dbDir = new File(serverDir, "databases");
dbDir.mkdirs();
server.activate();
OGlobalConfiguration.dumpConfiguration(System.out);
Thread.sleep(2000);
}
}
答案 0 :(得分：0)
嗨，这是因为当您向顶点添加边时，顶点本身会被修改以存储此信息，但是当有关边的信息存储在单独的对象中时，您可以在模式下工作。仅仅使用财产
-DridBag.embeddedToSbtreeBonsaiThreshold=true您将摆脱此异常。