Hibernate速度慢,无法获取Postgres连接
我在调试此问题时非常困难。每当我尝试与postgres建立连接时,都需要花费一分钟的时间。建立连接后,一切正常。我尝试禁用所有映射并且不加载任何映射,但是仍然需要花费很长时间来获取连接。我也尝试过禁用验证,没有区别。当我使用简单的简单JDBC连接时,它是瞬时的。Hibernate所做的事情需要花费大量时间,而我似乎无法缩小范围。任何输入,不胜感激!
Postgres驱动程序:
postgresql-9.1-901.jdbc4.jar
配置设置:
<hibernate-configuration> <session-factory>
<!-- properties -->
<property name="dialect">org.hibernate.dialect.PostgreSQLDialect</property>
<property name="connection.driver_class">org.postgresql.Driver</property>
<property name="connection.url">jdbc:postgresql://xxxx.com:5432/xxxxx</property>
<property name="connection.username">xxxxxxx</property>
<property name="connection.password">xxxxxxx</property>
</session-factory>
</hibernate-configuration>
代码中的其他设置:
config.setProperty("hibernate.hbm2ddl.auto", hbm2ddlMode); //config.setProperty("hibernate.cache.use_query_cache", "true");
config.setProperty("hibernate.cache.use_second_level_cache", "true");
//config.setProperty("hibernate.cache.region.factory_class", "net.sf.ehcache.hibernate.EhCacheRegionFactory");
config.setProperty("hibernate.cache.provider_class", "org.hibernate.cache.EhCacheProvider");
//config.setProperty("hibernate.cache.provider_class", "org.hibernate.cache.NoCacheProvider");
config.setProperty("hibernate.jdbc.fetch_size", "100");
config.setProperty("hibernate.jdbc.batch_size", "30");
config.setProperty("hibernate.jdbc.use_scrollable_resultset", "true");
config.setProperty("hibernate.connection.provider_class", "org.hibernate.connection.C3P0ConnectionProvider");
config.setProperty("hibernate.c3p0.acquire_increment", "1");
config.setProperty("hibernate.c3p0.idle_test_period", "0");
config.setProperty("hibernate.c3p0.min_size", "1");
config.setProperty("hibernate.c3p0.max_size", "2");
config.setProperty("hibernate.c3p0.timeout", "0");
config.setProperty("javax.persistence.validation.mode", "none");
这是发生延迟的代码段:
private SessionFactory buildSessionFactory() throws Exception { ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();
//Building session takes a whole minute without mappings!!!
sessionFactory = config.buildSessionFactory(serviceRegistry);
validateConnection();
return sessionFactory;
}
这是日志结果:
[main] 2012-04-09 10:40:32,823 110391 INFO C3P0ConnectionProvider - HHH000046: Connection properties: {user=hgaidb_test, password=****}
[main] 2012-04-09 10:40:32,823 110391 INFO C3P0ConnectionProvider - HHH000006:
Autocommit mode: false
[main] 2012-04-09 10:40:34,100 111668 DEBUG JdbcServicesImpl - Database ->
name : PostgreSQL
version : 8.3.3
major : 8
minor : 3
[main] 2012-04-09 10:40:34,101 111669 DEBUG JdbcServicesImpl - Driver ->
name : PostgreSQL Native Driver
version : PostgreSQL 9.1 JDBC4 (build 901)
major : 9
minor : 1
*******************************************************************************
// 1 MINUTE DELAY
*******************************************************************************
[main] 2012-04-09 10:40:34,102 111670 DEBUG JdbcServicesImpl - JDBC version : 4.
0
[main] 2012-04-09 10:41:21,632 159200 INFO Dialect - HHH000400: Using dialect:
org.hibernate.dialect.PostgreSQLDialect
*******************************************************************************
[main] 2012-04-09 10:41:21,669 159237 INFO LobCreatorBuilder - HHH000424: Disab
ling contextual LOB creation as createClob() method threw error : java.lang.refl
ect.InvocationTargetException
[main] 2012-04-09 10:41:21,814 159382 DEBUG SettingsFactory - Automatic flush du
ring beforeCompletion(): disabled
[main] 2012-04-09 10:41:21,814 159382 DEBUG SettingsFactory - Automatic session
close at end of transaction: disabled
[main] 2012-04-09 10:41:21,815 159383 DEBUG SettingsFactory - JDBC batch size: 3
0
[main] 2012-04-09 10:41:21,816 159384 DEBUG SettingsFactory - JDBC batch updates
for versioned data: disabled
[main] 2012-04-09 10:41:21,816 159384 DEBUG SettingsFactory - Scrollable result
sets: enabled
[main] 2012-04-09 10:41:21,817 159385 DEBUG SettingsFactory - Wrap result sets:
disabled
[main] 2012-04-09 10:41:21,818 159386 DEBUG SettingsFactory - JDBC3 getGenerated
Keys(): enabled
[main] 2012-04-09 10:41:21,818 159386 DEBUG SettingsFactory - JDBC result set fe
tch size: 100
[main] 2012-04-09 10:41:21,819 159387 DEBUG SettingsFactory - Connection release
mode: auto
[main] 2012-04-09 10:41:21,819 159387 INFO TransactionFactoryInitiator - HHH000
399: Using default transaction strategy (direct JDBC transactions)
[main] 2012-04-09 10:41:21,844 159412 DEBUG SettingsFactory - Default batch fetc
h size: 1
[main] 2012-04-09 10:41:21,844 159412 DEBUG SettingsFactory - Generate SQL with
comments: disabled
[main] 2012-04-09 10:41:21,845 159413 DEBUG SettingsFactory - Order SQL updates
by primary key: disabled
[main] 2012-04-09 10:41:21,846 159414 DEBUG SettingsFactory - Order SQL inserts
for batching: disabled
[main] 2012-04-09 10:41:21,846 159414 DEBUG SettingsFactory - Query translator:
org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory
[main] 2012-04-09 10:41:21,867 159435 INFO ASTQueryTranslatorFactory - HHH00039
7: Using ASTQueryTranslatorFactory
[main] 2012-04-09 10:41:21,867 159435 DEBUG SettingsFactory - Query language sub
stitutions: {}
[main] 2012-04-09 10:41:21,867 159435 DEBUG SettingsFactory - JPA-QL strict comp
liance: disabled
[main] 2012-04-09 10:41:21,868 159436 DEBUG SettingsFactory - Second-level cache
: enabled
[main] 2012-04-09 10:41:21,868 159436 DEBUG SettingsFactory - Query cache: disab
led
[main] 2012-04-09 10:41:21,869 159437 DEBUG SettingsFactory - Cache region facto
ry : org.hibernate.cache.internal.NoCachingRegionFactory
[main] 2012-04-09 10:41:21,872 159440 DEBUG SettingsFactory - org.hibernate.cach
e.internal.NoCachingRegionFactory did not provide constructor accepting java.uti
l.Properties; attempting no-arg constructor.
[main] 2012-04-09 10:41:21,873 159441 DEBUG SettingsFactory - Optimize cache for
minimal puts: disabled
[main] 2012-04-09 10:41:21,873 159441 DEBUG SettingsFactory - Structured second-
level cache entries: disabled
[main] 2012-04-09 10:41:21,873 159441 DEBUG SettingsFactory - Statistics: disabl
ed
[main] 2012-04-09 10:41:21,874 159442 DEBUG SettingsFactory - Deleted entity syn
thetic identifier rollback: disabled
[main] 2012-04-09 10:41:21,874 159442 DEBUG SettingsFactory - Default entity-mod
e: pojo
[main] 2012-04-09 10:41:21,875 159443 DEBUG SettingsFactory - Named query checki
ng : enabled
[main] 2012-04-09 10:41:21,875 159443 DEBUG SettingsFactory - Check Nullability
in Core (should be disabled when Bean Validation is on): enabled
[main] 2012-04-09 10:41:21,876 159444 DEBUG SettingsFactory - multi-tenancy stra
tegy : NONE
我对此进行了更多的研究,逐步调试器。我的类路径中没有所有源代码,但仍然可以看到变量。等待一分钟后,Hibernate正在查询pg_catalog.pg_type表:
[SELECT typname FROM pg_catalog.pg_type WHERE oid = , ]
回答:
我修复了它=)我真的必须扎根寻找这个问题的答案。基本上,它涉及到加载元数据和JDBC驱动程序。它正在加载所有元数据,包括sql列旁边的注释和其他各种构造,这些都是操作所不需要的。我不知道为什么默认情况下会启用此功能,但是除非明确需要,否则您应该关闭此功能:
config.setProperty("hibernate.temp.use_jdbc_metadata_defaults","false");
立即连接!
我可以找到的唯一信息是在代码中:
107 // 'hibernate.temp.use_jdbc_metadata_defaults' is a temporary magic value.108 // The need for it is intended to be alleviated with future development, thus it is
109 // not defined as an Environment constant...
110 //
111 // it is used to control whether we should consult the JDBC metadata to determine
112 // certain Settings default values; it is useful to *not* do this when the database
113 // may not be available (mainly in tools usage).
114 boolean useJdbcMetadata = ConfigurationHelper.getBoolean( "hibernate.temp.use_jdbc_metadata_defaults", configValues, true );
http://grepcode.com/file/repo1.maven.org/maven2/org.hibernate/hibernate-core/4.1.1.Final/org/hibernate/engine/jdbc/internal/JdbcServicesImpl.java#JdbcServicesImpl
以上是 Hibernate速度慢,无法获取Postgres连接 的全部内容, 来源链接: utcz.com/qa/409704.html