今天，公司项目某个模块的导出报如下错误：

  1. HTTP Status 500 – Internal Server Error
  2. Type Exception Report
  3.  
  4. Message Handler dispatch failed; nested exception is java.lang.OutOfMemoryError: GC overhead limit exceeded
  5.  
  6. Description The server encountered an unexpected condition that prevented it from fulfilling the request.
  7.  
  8. Exception
  9.  
  10. org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.OutOfMemoryError: GC overhead limit exceeded
  11.     org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1006)
  12.     org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
  13.     org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978)
  14.     org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:881)
  15.     javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
  16.     org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:855)
  17.     javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
  18.     org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
  19.     org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
  20.     org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
  21.     org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
  22.     org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
  23.     org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
  24.     org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
  25.     org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
  26.     org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
  27.     org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
  28.     org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:387)
  29.     org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
  30.     org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
  31.     org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357)
  32.     org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270)
  33.     com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:209)
  34.     com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:244)
  35.     org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
  36.     org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  37. Root Cause
  38.  
  39. java.lang.OutOfMemoryError: GC overhead limit exceeded
  40.     java.util.Arrays.copyOf(Arrays.java:3332)
  41.     java.lang.AbstractStringBuilder.ensureCapacityInternal(AbstractStringBuilder.java:124)
  42.     java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:448)
  43.     java.lang.StringBuilder.append(StringBuilder.java:136)
  44.     org.apache.ibatis.executor.resultset.ResultSetWrapper.getMapKey(ResultSetWrapper.java:176)
  45.     org.apache.ibatis.executor.resultset.ResultSetWrapper.getMappedColumnNames(ResultSetWrapper.java:158)
  46.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.applyPropertyMappings(DefaultResultSetHandler.java:428)
  47.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.getRowValue(DefaultResultSetHandler.java:916)
  48.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.applyNestedResultMappings(DefaultResultSetHandler.java:963)
  49.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.getRowValue(DefaultResultSetHandler.java:918)
  50.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValuesForNestedResultMap(DefaultResultSetHandler.java:881)
  51.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValues(DefaultResultSetHandler.java:328)
  52.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSet(DefaultResultSetHandler.java:303)
  53.     org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSets(DefaultResultSetHandler.java:196)
  54.     org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:64)
  55.     org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79)
  56.     sun.reflect.GeneratedMethodAccessor370.invoke(Unknown Source)
  57.     sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  58.     java.lang.reflect.Method.invoke(Method.java:498)
  59.     org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:63)
  60.     com.sun.proxy.$Proxy1141.query(Unknown Source)
  61.     org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63)
  62.     org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:326)
  63.     org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
  64.     org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
  65.     org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83)
  66.     sun.reflect.GeneratedMethodAccessor369.invoke(Unknown Source)
  67.     sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  68.     java.lang.reflect.Method.invoke(Method.java:498)
  69.     org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:63)
  70.     com.sun.proxy.$Proxy1140.query(Unknown Source)
  71.     org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148)
  72.     org.springframework.remoting.support.RemoteInvocationUtils.fillInClientStackTraceIfPossible(RemoteInvocationUtils.java:45)
  73.     org.springframework.remoting.support.RemoteInvocationResult.recreate(RemoteInvocationResult.java:156)
  74.     org.springframework.remoting.support.RemoteInvocationBasedAccessor.recreateRemoteInvocationResult(RemoteInvocationBasedAccessor.java:85)
  75.     org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor.invoke(HttpInvokerClientInterceptor.java:162)
  76.     org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  77.     org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212)
  78.     com.sun.proxy.$Proxy765.listInvoiceDetail(Unknown Source)
  79.     com.csw.purchase.controller.InvoiceQueryController.exportAll(InvoiceQueryController.java:174)
  80.     com.csw.purchase.controller.InvoiceQueryController$$FastClassBySpringCGLIB$$f1d52ef0.invoke(<generated>)
  81.     org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
  82.     org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:747)
  83.     org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
  84.     org.apache.shiro.spring.security.interceptor.AopAllianceAnnotationsAuthorizingMethodInterceptor$1.proceed(AopAllianceAnnotationsAuthorizingMethodInterceptor.java:82)
  85.     org.apache.shiro.authz.aop.AuthorizingMethodInterceptor.invoke(AuthorizingMethodInterceptor.java:39)
  86.     org.apache.shiro.spring.security.interceptor.AopAllianceAnnotationsAuthorizingMethodInterceptor.invoke(AopAllianceAnnotationsAuthorizingMethodInterceptor.java:115)
  87.     org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  88.     org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:689)
  89.     com.csw.purchase.controller.InvoiceQueryController$$EnhancerBySpringCGLIB$$b3090726.exportAll(<generated>)
  90.     sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  91.     sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
  92.     sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  93.     java.lang.reflect.Method.invoke(Method.java:498)
  94.     org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)
  95.     org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
  96.     org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
  97.     org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:870)
  98.     org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:776)
  99.     org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
  100.     org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
  101.     org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
  102.     org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978)
  103.     org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:881)
  104.     javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
  105.     org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:855)
  106.     javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
  107.     org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
  108.     org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
  109.     org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
  110.     org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
  111.     org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
  112.     org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
  113.     org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
  114.     org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
  115.     org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
  116.     org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
  117.     org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:387)
  118.     org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
  119.     org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
  120.     org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357)
  121.     org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270)
  122.     com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:209)
  123.     com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:244)
  124.     org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
  125.     org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  126. Note The full stack trace of the root cause is available in the server logs.
  127.  
  128. Apache Tomcat/8.5.24

内存溢出，导出前需要查询的sql如下：

  1. SELECT
  2.     pid.id,
  3.     pid.materials_id,
  4.     pid.invoice_id,
  5.     pid.inform_order_detail_id,
  6.     pid.unit_price,
  7.     pid.invoice_amt,
  8.     pid.remark,
  9.     pid.biz_status,
  10.     pid.version,
  11.     pid.is_deleted,
  12.     pid.create_user,
  13.     pid.gmt_create,
  14.     pid.create_user_id,
  15.     pid.modified_user,
  16.     pid.gmt_modified,
  17.     pid.materials_release_id,
  18.     m.id m_id,
  19.     m.item_id m_item_id,
  20.     m.code m_code,
  21.     m.unit m_unit,
  22.     m.name m_name,
  23.     m.short_code m_short_code,
  24.     m.primary_uom m_primary_uom,
  25.     m.key_component_flag m_key_component_flag,
  26.     m.materials_type m_materials_type,
  27.     m.classification m_classification,
  28.     m.is_examine m_is_examine,
  29.     m.item_status m_item_status,
  30.     m.is_examine_item m_is_examine_item,
  31.     m.purchase_type m_purchase_type,
  32.     m.gmt_modified m_gmt_modified,
  33.     m.modified_user m_modified_user,
  34.     iiod.id iiod_id,
  35.     iiod.invoice_inform_order_id iiod_invoice_inform_order_id,
  36.     iiod.materials_id iiod_materials_id,
  37.     iiod.invoice_qty iiod_invoice_qty,
  38.     iiod.unit_price iiod_unit_price,
  39.     iiod.dispense_num iiod_dispense_num,
  40.     iiod.package_deal_code iiod_package_deal_code,
  41.     iiod.current_differ_price iiod_current_differ_price,
  42.     i.id i_id,
  43.     i.code i_code,
  44.     i.supplier_id i_supplier_id,
  45.     i.invoice_val i_invoice_val,
  46.     i.old_code i_old_code,
  47.     i.invoice_tax_val i_invoice_tax_val,
  48.     i.tax_amount i_tax_amount,
  49.     i.vmi_type i_vmi_type,
  50.     i.invoice_abstract i_invoice_abstract,
  51.     i.general_ledger_date i_general_ledger_date,
  52.     i.input_time i_input_time,
  53.     i.is_hand_dispose i_is_hand_dispose,
  54.     i.invoice_status i_invoice_status,
  55.     i.organization_id i_organization_id,
  56.     i.invoice_type i_invoice_type,
  57.     s.id s_id,
  58.     s.name s_name,
  59.     s.code s_code,
  60.     s.short_code s_short_code,
  61.     s.TYPE s_type,
  62.     s.main_product s_main_product,
  63.     s.tax_reg_num s_tax_reg_num,
  64.     iio.id iio_id,
  65.     iio.code iio_code,
  66.     iio.end_date iio_end_date,
  67.     iio.department_id iio_department_id,
  68.     iio.supplier_id iio_supplier_id,
  69.     iio.drawer iio_drawer,
  70.     iio.vmi_type iio_vmi_type,
  71.     iio.invoice_audit_status iio_invoice_audit_status,
  72.     iio.organization_id iio_organization_id,
  73.     iio.inform_order_type iio_inform_order_type,
  74.     it.id it_id,
  75.     it.invoice_id it_invoice_id,
  76.     it.tax_rate it_tax_rate,
  77.     it.tax_amount it_tax_amount
  78. FROM
  79.     p_invoice_detail pid
  80.     LEFT JOIN s_materials m ON pid.materials_id = m.id
  81.     LEFT JOIN p_invoice_inform_order_detail iiod ON pid.inform_order_detail_id = iiod.id
  82.     LEFT JOIN p_invoice_inform_order iio ON iiod.invoice_inform_order_id = iio.id
  83.     LEFT JOIN p_invoice i ON pid.invoice_id = i.id
  84.     LEFT JOIN p_invoice_tax it ON i.id = it.invoice_id
  85.     LEFT JOIN s_supplier s ON s.id = i.supplier_id
  86. WHERE
  87.     i.is_deleted = 0

其中表p_invoice_detail 中大概34W条数据，p_invoice_inform_order_detail中大概14W条数据，其它表中数据不超1W条，于是博主各种折腾，建索引，调整连接顺序等，都不起作用，博主用的navicat，每次查询我的naviicat就罢工，报unknown internal error (A70529121901)  bad  allocation，没办法，只好一个表一个表的排除，最后发现，左连接p_invoice_inform_order_detail 表后就会出现上述问题，其它表都没事，于是博主单独查询这张表发现也很慢：

用了37.704s只查询出8300条记录（表中共有约14W条数据），但是同样的查询有34W条数据的表p_invoice_detail却用了12.640s就全部查询出来了，博主就奇怪了，于是一个字段一个字段的试，终于发现是表p_invoice_inform_order_detail中的dispose_num字段导致的，后来发现该字段为clob类型，问题定位就好说了，上网查询发现将clob字段转为string类型再查询出来会提高效率，于是照做：将最开始的iiod.dispense_num修改为dbms_lob.substr(iiod.dispense_num,dbms_lob.getlength(iiod.dispense_num),1) dispense_num：

  1. SELECT
  2.     pid.id,
  3.     pid.materials_id,
  4.     pid.invoice_id,
  5.     pid.inform_order_detail_id,
  6.     pid.unit_price,
  7.     pid.invoice_amt,
  8.     pid.remark,
  9.     pid.biz_status,
  10.     pid.version,
  11.     pid.is_deleted,
  12.     pid.create_user,
  13.     pid.gmt_create,
  14.     pid.create_user_id,
  15.     pid.modified_user,
  16.     pid.gmt_modified,
  17.     pid.materials_release_id,
  18.     m.id m_id,
  19.     m.item_id m_item_id,
  20.     m.code m_code,
  21.     m.unit m_unit,
  22.     m.name m_name,
  23.     m.short_code m_short_code,
  24.     m.primary_uom m_primary_uom,
  25.     m.key_component_flag m_key_component_flag,
  26.     m.materials_type m_materials_type,
  27.     m.classification m_classification,
  28.     m.is_examine m_is_examine,
  29.     m.item_status m_item_status,
  30.     m.is_examine_item m_is_examine_item,
  31.     m.purchase_type m_purchase_type,
  32.     m.gmt_modified m_gmt_modified,
  33.     m.modified_user m_modified_user,
  34.     iiod.id iiod_id,
  35.     iiod.invoice_inform_order_id iiod_invoice_inform_order_id,
  36.     iiod.materials_id iiod_materials_id,
  37.     iiod.invoice_qty iiod_invoice_qty,
  38.     iiod.unit_price iiod_unit_price,
  39.     dbms_lob.substr(iiod.dispense_num,dbms_lob.getlength(iiod.dispense_num),1) dispense_num,
  40.     iiod.package_deal_code iiod_package_deal_code,
  41.     iiod.current_differ_price iiod_current_differ_price,
  42.     i.id i_id,
  43.     i.code i_code,
  44.     i.supplier_id i_supplier_id,
  45.     i.invoice_val i_invoice_val,
  46.     i.old_code i_old_code,
  47.     i.invoice_tax_val i_invoice_tax_val,
  48.     i.tax_amount i_tax_amount,
  49.     i.vmi_type i_vmi_type,
  50.     i.invoice_abstract i_invoice_abstract,
  51.     i.general_ledger_date i_general_ledger_date,
  52.     i.input_time i_input_time,
  53.     i.is_hand_dispose i_is_hand_dispose,
  54.     i.invoice_status i_invoice_status,
  55.     i.organization_id i_organization_id,
  56.     i.invoice_type i_invoice_type,
  57.     s.id s_id,
  58.     s.name s_name,
  59.     s.code s_code,
  60.     s.short_code s_short_code,
  61.     s.TYPE s_type,
  62.     s.main_product s_main_product,
  63.     s.tax_reg_num s_tax_reg_num,
  64.     iio.id iio_id,
  65.     iio.code iio_code,
  66.     iio.end_date iio_end_date,
  67.     iio.department_id iio_department_id,
  68.     iio.supplier_id iio_supplier_id,
  69.     iio.drawer iio_drawer,
  70.     iio.vmi_type iio_vmi_type,
  71.     iio.invoice_audit_status iio_invoice_audit_status,
  72.     iio.organization_id iio_organization_id,
  73.     iio.inform_order_type iio_inform_order_type,
  74.     it.id it_id,
  75.     it.invoice_id it_invoice_id,
  76.     it.tax_rate it_tax_rate,
  77.     it.tax_amount it_tax_amount
  78. FROM
  79.     p_invoice_detail pid
  80.     LEFT JOIN s_materials m ON pid.materials_id = m.id
  81.     LEFT JOIN p_invoice_inform_order_detail iiod ON pid.inform_order_detail_id = iiod.id
  82.     LEFT JOIN p_invoice_inform_order iio ON iiod.invoice_inform_order_id = iio.id
  83.     LEFT JOIN p_invoice i ON pid.invoice_id = i.id
  84.     LEFT JOIN p_invoice_tax it ON i.id = it.invoice_id
  85.     LEFT JOIN s_supplier s ON s.id = i.supplier_id
  86. WHERE
  87.     i.is_deleted = 0

修改后查询，发现还是很慢，于是将其它不需要的字段去掉，调整为：

  1. SELECT
  2.   i.id,
  3.     i.gmt_create,
  4.     i.code,
  5.             i.invoice_tax_val,
  6.             m.code materials_code,
  7.             m.name materials_name,
  8.              s.code supplier_code,
  9.             s.name supplier_name,
  10.             pid.unit_price,
  11.              it.tax_rate,
  12.             i.tax_amount,
  13.           iiod.current_differ_price,
  14.             pid.invoice_amt,
  15.             i.invoice_val,
  16.             pid.unit_price * pid.invoice_amt total_money,
  17.             dbms_lob.substr(iiod.dispense_num,dbms_lob.getlength(iiod.dispense_num),1) dispense_num,
  18.             decode(i.invoice_type,'','供应商平台','','发票平台')
  19.  
  20. FROM
  21.     p_invoice_detail pid
  22.     LEFT JOIN p_invoice i ON pid.invoice_id = i.id
  23.     LEFT JOIN s_materials m ON pid.materials_id = m.id
  24.     LEFT JOIN p_invoice_inform_order_detail iiod ON pid.inform_order_detail_id = iiod.id
  25.     LEFT JOIN p_invoice_inform_order iio ON iiod.invoice_inform_order_id = iio.id
  26.     LEFT JOIN p_invoice_tax it ON i.id = it.invoice_id
  27.     LEFT JOIN s_supplier s ON s.id = i.supplier_id
  28. WHERE
  29.     i.is_deleted = 0

这次总算不报错了，虽然查询单速度还是有点慢，但还能接受：

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