我有一个专用服务器来托管我的应用程序，它有一个 mysql、tomcat 和一个为 solr 服务器运行的专用服务器应用程序。服务器有一个 64gb 硬盘和 4gb 内存。
所以现在我的数据库增加到了 14gb，solr 索引大小增加到了 4.5gb，堆大小从 tomcat 增加到了 4gb，但是当我尝试执行数据库操作时，我得到了 jave 堆空间异常并且具有小数据库条目的相同应用程序运行良好。
那么如何在不妨碍我当前正在运行的应用程序的情况下摆脱异常，以及可能的解决方案是什么。
这个异常是由于我的应用程序中使用的休眠查询引起的吗？如果是的话，应该做哪些改变，这样应用程序就不会再次面临这个异常，因为我的数据库和 solr 可能打算增长。
任何建议都是可观的。提前致谢
异常跟踪：
[ERROR] Exception while dispatching incoming RPC call
x.x.action.StandardDispatchService.execute(x.x.action.Action) throws x.x.action.exception.DispatchException' threw an unexpected exception: java.lang.OutOfMemoryError: Java heap space
at com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java:385)
at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:588)
at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:208)
at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:248)
at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at com.google.inject.servlet.ServletDefinition.doService(ServletDefinition.java:263)
at com.google.inject.servlet.ServletDefinition.service(ServletDefinition.java:178)
at com.google.inject.servlet.ManagedServletPipeline.service(ManagedServletPipeline.java:91)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:62)
at com.google.inject.servlet.ManagedFilterPipeline.dispatch(ManagedFilterPipeline.java:118)
at com.google.inject.servlet.GuiceFilter.doFilter(GuiceFilter.java:113)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1088)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:360)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:729)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.handler.RequestLogHandler.handle(RequestLogHandler.java:49)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:324)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:647)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:395)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488)
Caused by: java.lang.OutOfMemoryError: Java heap space
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2931)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2871)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3414)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:910)
at com.mysql.jdbc.MysqlIO.nextRow(MysqlIO.java:1405)
at com.mysql.jdbc.MysqlIO.readSingleRowSet(MysqlIO.java:2816)
at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:467)
at com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:2510)
at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:1746)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2135)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2542)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1734)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1885)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1869)
at org.hibernate.loader.Loader.doQuery(Loader.java:718)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
at org.hibernate.loader.Loader.loadEntity(Loader.java:1953)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:86)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:76)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3270)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:496)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:477)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:227)
at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:285)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:152)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:1080)
at org.hibernate.impl.SessionImpl.internalLoad(SessionImpl.java:1028)
at org.hibernate.type.EntityType.resolveIdentifier(EntityType.java:623)
at org.hibernate.type.EntityType.resolve(EntityType.java:431)
at org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:140)
[ERROR] Out of memory; to increase the amount of memory, use the -Xmx flag at startup (java -Xmx128M ...)
[ERROR] 500 - POST /x/dispatch (x) 57 bytes
Request headers
Host: x
User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20100101 Firefox/16.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive
Referer: http://x/x.html
X-GWT-Permutation: HostedMode
X-GWT-Module-Base: http:/x/x/
Content-Type: text/x-gwt-rpc; charset=utf-8
Content-Length: 6554
Pragma: no-cache
Cache-Control: no-cache
Cookie: JSESSIONID=685w5nqkzsap
Response headers
Content-Type: text/plain