Spring boot 对于带有camunda bpm spring boot starter rest hibernate属性的项目，其指标会受到影响，输出工作不正常（仅部分）

Spring Boot应用程序使用为应用程序提供Hibernate/Entity Manager的

camunda bpm Spring Boot starter rest

。为了设置Spring Boot Actuator Prometheus（Actuator）指标，我们在

应用程序中添加了这一行。properties

：

spring.jpa.properties.hibernate.generate_statistics=true

之后，以下详细信息开始输出到标准输出：

2020-11-16 16:14:49.923  INFO 1345328 --- [ingJobExecutor]] i.StatisticalLoggingSessionEventListener : Session Metrics {
    547400 nanoseconds spent acquiring 1 JDBC connections;
    0 nanoseconds spent releasing 0 JDBC connections;
    0 nanoseconds spent preparing 0 JDBC statements;
    0 nanoseconds spent executing 0 JDBC statements;
    0 nanoseconds spent executing 0 JDBC batches;
    0 nanoseconds spent performing 0 L2C puts;
    0 nanoseconds spent performing 0 L2C hits;
    0 nanoseconds spent performing 0 L2C misses;
    0 nanoseconds spent executing 0 flushes (flushing a total of 0 entities and 0 collections);
    0 nanoseconds spent executing 0 partial-flushes (flushing a total of 0 entities and 0 collections)
}

除了获取非零的JDBC连接外，它们都不包含其他内容的统计信息，而JDBC语句实际上是准备和执行的。那么，触发此类日志的事件是什么，而实际上从未写入执行的jdbc语句的CONU

在正确配置的Spring Boot应用程序中，这些内容会按照预期进行记录，如：

17:18:59.313 [http-nio-8080-exec-3] INFO  o.h.e.i.StatisticalLoggingSessionEventListener - Session Metrics {
    1063300 nanoseconds spent acquiring 1 JDBC connections;
    0 nanoseconds spent releasing 0 JDBC connections;
    117600 nanoseconds spent preparing 1 JDBC statements;
    739400 nanoseconds spent executing 1 JDBC statements;
    0 nanoseconds spent executing 0 JDBC batches;
    0 nanoseconds spent performing 0 L2C puts;
    0 nanoseconds spent performing 0 L2C hits;
    0 nanoseconds spent performing 0 L2C misses;
    1182400 nanoseconds spent executing 1 flushes (flushing a total of 14 entities and 0 collections);
    5700 nanoseconds spent executing 1 partial-flushes (flushing a total of 0 entities and 0 collections)

至于指标，输出到/actuator/prometheus，它看起来也缺少一些细节，但根本不是空的，有一些相互矛盾的输出：

# HELP hibernate_transactions_total The number of transactions we know to have been successful
# TYPE hibernate_transactions_total counter
hibernate_transactions_total{entityManagerFactory="entityManagerFactory",result="success",} 2231.0
hibernate_transactions_total{entityManagerFactory="entityManagerFactory",result="failure",} 1.0
# HELP hibernate_collections_recreates_total The number of collections recreated
# TYPE hibernate_collections_recreates_total counter
hibernate_collections_recreates_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_cache_natural_id_puts_total The number of cacheable naturalId lookups put in cache
# TYPE hibernate_cache_natural_id_puts_total counter
hibernate_cache_natural_id_puts_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_cache_update_timestamps_requests_total The number of timestamps successfully retrieved from cache
# TYPE hibernate_cache_update_timestamps_requests_total counter
hibernate_cache_update_timestamps_requests_total{entityManagerFactory="entityManagerFactory",result="miss",} 0.0
hibernate_cache_update_timestamps_requests_total{entityManagerFactory="entityManagerFactory",result="hit",} 0.0
# HELP hibernate_sessions_open_total Sessions opened
# TYPE hibernate_sessions_open_total counter
hibernate_sessions_open_total{entityManagerFactory="entityManagerFactory",} 2232.0
# HELP hibernate_entities_inserts_total The number of entity inserts
# TYPE hibernate_entities_inserts_total counter
hibernate_entities_inserts_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_cache_update_timestamps_puts_total The number of timestamps put in cache
# TYPE hibernate_cache_update_timestamps_puts_total counter
hibernate_cache_update_timestamps_puts_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_cache_query_puts_total The number of cacheable queries put in cache
# TYPE hibernate_cache_query_puts_total counter
hibernate_cache_query_puts_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_statements_total The number of prepared statements that were acquired
# TYPE hibernate_statements_total counter
hibernate_statements_total{entityManagerFactory="entityManagerFactory",status="closed",} 0.0
hibernate_statements_total{entityManagerFactory="entityManagerFactory",status="prepared",} 0.0
# HELP hibernate_second_level_cache_puts_total The number of cacheable entities/collections put in the cache
# TYPE hibernate_second_level_cache_puts_total counter
hibernate_second_level_cache_puts_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_second_level_cache_requests_total The number of cacheable entities/collections successfully retrieved from the cache
# TYPE hibernate_second_level_cache_requests_total counter
hibernate_second_level_cache_requests_total{entityManagerFactory="entityManagerFactory",result="miss",} 0.0
hibernate_second_level_cache_requests_total{entityManagerFactory="entityManagerFactory",result="hit",} 0.0
# HELP hibernate_entities_loads_total The number of entity loads
# TYPE hibernate_entities_loads_total counter
hibernate_entities_loads_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_entities_deletes_total The number of entity deletes
# TYPE hibernate_entities_deletes_total counter
hibernate_entities_deletes_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_query_natural_id_executions_max_seconds The maximum query time for naturalId queries executed against the database
# TYPE hibernate_query_natural_id_executions_max_seconds gauge
hibernate_query_natural_id_executions_max_seconds{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_cache_natural_id_requests_total The number of cached naturalId lookups successfully retrieved from cache
# TYPE hibernate_cache_natural_id_requests_total counter
hibernate_cache_natural_id_requests_total{entityManagerFactory="entityManagerFactory",result="miss",} 0.0
hibernate_cache_natural_id_requests_total{entityManagerFactory="entityManagerFactory",result="hit",} 0.0
# HELP hibernate_sessions_closed_total Sessions closed
# TYPE hibernate_sessions_closed_total counter
hibernate_sessions_closed_total{entityManagerFactory="entityManagerFactory",} 2232.0
# HELP hibernate_flushes_total The global number of flushes executed by sessions (either implicit or explicit)
# TYPE hibernate_flushes_total counter
hibernate_flushes_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_query_executions_total The number of executed queries
# TYPE hibernate_query_executions_total counter
hibernate_query_executions_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_collections_fetches_total The number of collection fetches
# TYPE hibernate_collections_fetches_total counter
hibernate_collections_fetches_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_optimistic_failures_total The number of StaleObjectStateExceptions that have occurred
# TYPE hibernate_optimistic_failures_total counter
hibernate_optimistic_failures_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_entities_fetches_total The number of entity fetches
# TYPE hibernate_entities_fetches_total counter
hibernate_entities_fetches_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_cache_query_requests_total The number of cached queries successfully retrieved from cache
# TYPE hibernate_cache_query_requests_total counter
hibernate_cache_query_requests_total{entityManagerFactory="entityManagerFactory",result="miss",} 0.0
hibernate_cache_query_requests_total{entityManagerFactory="entityManagerFactory",result="hit",} 0.0
# HELP hibernate_collections_deletes_total The number of collection deletes
# TYPE hibernate_collections_deletes_total counter
hibernate_collections_deletes_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_query_executions_max_seconds The time of the slowest query
# TYPE hibernate_query_executions_max_seconds gauge
hibernate_query_executions_max_seconds{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_connections_obtained_total Get the global number of connections asked by the sessions (the actual number of connections used may be much smaller depending whether you use a connection pool or not)
# TYPE hibernate_connections_obtained_total counter
hibernate_connections_obtained_total{entityManagerFactory="entityManagerFactory",} 2232.0
# HELP hibernate_entities_updates_total The number of entity updates
# TYPE hibernate_entities_updates_total counter
hibernate_entities_updates_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_collections_loads_total The number of collection loads
# TYPE hibernate_collections_loads_total counter
hibernate_collections_loads_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_collections_updates_total The number of collection updates
# TYPE hibernate_collections_updates_total counter
hibernate_collections_updates_total{entityManagerFactory="entityManagerFactory",} 0.0
# HELP hibernate_query_natural_id_executions_total The number of naturalId queries executed against the database
# TYPE hibernate_query_natural_id_executions_total counter
hibernate_query_natural_id_executions_total{entityManagerFactory="entityManagerFactory",} 0.0

因此，只有sessions计数器是真实的，而其他计数器则不存在

hibernate_query_executions_max_seconds{entityManagerFactory="entityManagerFactory",} 0.0

这里看起来不一致，如果有这么多事务，那么最慢的一个怎么可能是0-long

所以，这很可能是因为

EntityManager

使用bpm camunda starter进行初始化，而不是我们的应用程序bean本身？如何解决这一问题，并让那些优秀的人才被正确地挑选出来？也许度量收集器可以以某种方式注入到那里

UPD：

我尝试检查EntitymanagerFactory中的内容，并尝试使用新值更新它。根据标准，它要求hibernate.metrics为true

package com.example.demo;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.persistence.EntityManagerFactory;
import java.util.logging.Logger;

@Component
public class HibernatePropertiesInterceptor {

    private static final Logger LOG
            = Logger.getLogger(HibernatePropertiesInterceptor.class.getName());

    @Autowired
    private EntityManagerFactory entityManagerFactory;

    @PostConstruct
    public void init() {
        LOG.info("Changing hibernate metrics-related properties");
        LOG.info("Current hibernate properties are "+entityManagerFactory.getProperties().keySet());
        LOG.info("Current hibernate.generate_statistics value is "+entityManagerFactory.getProperties().get("hibernate.generate_statistics"));
        entityManagerFactory.getProperties().put("hibernate.generate_statistics","true");
        LOG.info("Updated hibernate properties are "+entityManagerFactory.getProperties().keySet());
        LOG.info("Updated hibernate.generate_statistics value is "+entityManagerFactory.getProperties().get("hibernate.generate_statistics"));
    }
}

---

事实证明，

hibernate.metrics

已经是真的了！所以，我不知道要检查什么以及如何使用仪器来显示真实的统计数据。看起来，

EntityManager

真的做到了预期的所有事情，所以这可能是因为camunda在大多数情况下都不使用实体管理器？或者什么？

我还认为这是因为

EntityManager

不是由spring上下文管理的bean。您是否可以尝试使用

EntityManager

的bean创建配置类，就像从

ProcessEngine

获取在

SpringProcessEngineServiceConfiguration

中创建的其他bean一样

如下图所示：

@Bean
public EntityManagerFactory getEntityManagerFactory(ProcessEngineConfiguration engineConfiguration) {
    return engineConfiugration.getSessionFactories().get(EntityManagerSession.class); 

}

---

另外，这只是一个尝试和错误，我还没有尝试过，但至少它应该给你提供

EntityManager

的bean。请参阅

ProcessEngineConfigurationImpl.java

类的

initJpa（）

方法。

与camunda engine 7.13.0一样，没有

.getSessionFactorys（）

那么访问会话工厂的另一种方法是什么呢？检查ProcessEngineConfigurationImpl，它应该有初始化jpa的方法和获取它的方法。只需使用getter返回bean即可。我已经尝试过这个肮脏的黑客（接口本身缺少getSessionFactory，只有impl）：

@bean

公共EntityManager工厂getEntityManager工厂（ProcessEngineConfiguration engineConfiguration）{return（EntityManager工厂）（ProcessEngineConfigurationImpl）engineConfiguration）.GetSessionFactorys（）.get（EntityManagerSession.class）；}

现在获取循环引用错误：为了调查历史，请保留它确定。。我们会回复您：）