国产xxxx99真实实拍_久久不雅视频_高清韩国a级特黄毛片_嗯老师别我我受不了了小说

資訊專欄INFORMATION COLUMN

記一次線上bug處理-mybatis一級緩存引起

sean / 1212人閱讀

摘要：問題線上定時任務計算出的金額不對定位問題查看日志好像也執行了但是金額為什么和數據庫的表里的不一致再查整個的定時任務日志日切日期

問題：

線上riskProvision定時任務,計算出的金額不對

定位問題：

查看日志

4.13 riskProvision
    2017-04-13 01:10:00.009 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] from current transaction
    2017-04-13 01:10:00.010 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] for iBATIS operation
    2017-04-13 01:10:00.010 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28]
    2017-04-13 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] from current transaction
    2017-04-13 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] for iBATIS operation
    2017-04-13 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28]
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Creating SqlSession with JDBC Connection [com.alibaba.druid.proxy.jdbc.ConnectionProxyImpl@43c10cbc]
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.Connection] DEBUG ooo Connection Opened
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SpringManagedTransaction] DEBUG JDBC Connection [com.alibaba.druid.proxy.jdbc.ConnectionProxyImpl@43c10cbc] will be managed by Spring
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Registering transaction synchronization for SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1159e5ac]
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1159e5ac] for iBATIS operation
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.PreparedStatement] DEBUG ==> Executing: select sum(a.TRAN_AMT) from FIN_FUND_TRAN a join outcome_flow b on a.pt_no = b.pt_no and a.ser_no = b.bus_ser where "1" = a.TRAN_ACC and a.TRAN_REA = "1" and (b.RECO_STATE = "U"or b.RECO_STATE = "0" or b.RECO_STATE = "5") and a.pt_no = ?
    2017-04-13 01:10:00.012 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.PreparedStatement] DEBUG ==> Parameters: 002(String)
    2017-04-13 01:10:00.014 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.ResultSet] DEBUG <== Columns: 1

好像也執行了,但是金額為什么和數據庫的表里的不一致,再查整個的定時任務日志

4.13 cron
2017-04-13 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] from current transaction
2017-04-13 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] for iBATIS operation
2017-04-13 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28]
2017-04-13 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [net.tangdi.gxseas.service.AutoRecon] INFO === 日切日期：2017-04-07
2017-04-13 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [net.tangdi.gxseas.service.AutoRecon] INFO 任務號:A,任務執行步驟:A01,日切日期:20170407

4月13日應該執行4.12日的,為什么執行了4.07日的了?
查下數據庫定時任務日期控制表也是4,12,詭異啊?
不對,日志為什么沒有執行的sql記錄呢?
異常的話也不應該執行下去啊,莫名其妙,陷入了無頭緒的狀態.
因為mybatis的調用時用的第三方小廠家封裝框架,出于對于它的不信任,看起了源碼,在BaseExecutor發現看玄機

public List query(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler) throws SQLException {
  ErrorContext.instance().resource(ms.getResource()).activity("executing a query").object(ms.getId());
  if (closed) throw new ExecutorException("Executor was closed.");
 
  // Flush the internal cache is force is true
  if (ms.isFlushCacheRequired()) {
      clearLocalCache();
  }
  List list;
  try {
    queryStack++;
    CacheKey key = createCacheKey(ms, parameter, rowBounds);
    list = resultHandler == null ? (List) localCache.getObject(key) : null;
    if (list != null) {
      handleLocallyCachedOutputParameters(ms, key, parameter);
    } else {
      list = queryFromDatabase(ms, parameter, rowBounds, resultHandler, key);
    }
  } finally {
    queryStack--;
  }
  if (queryStack == 0) {
    for (DeferredLoad deferredLoad : deferredLoads) {
      deferredLoad.load();
    }
  }
  return list;
}

調用方resultHandler傳入的默認全是null,說明它會緩存拿.
因為上面的sql都沒有參數,key是一定的,所以第二次之后會查緩存，但是數據時會變的,造成緩存和數據庫的數據不一致.
繼續看mybatis源碼,發現localCache是SqlSession的成員變量.那么就可以斷定如果相同的sql在同一個SqlSession執行,就會命中緩存,為了證實我的猜想,繼續翻日志

4.10 rishProvision
2017-04-10 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] from current transaction
2017-04-10 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] for iBATIS operation
2017-04-10 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.PreparedStatement] DEBUG ==> Executing: SELECT PT_NO, ACC_AMT, BOON_AMT, CUST_AMT, PRO_AMT, FEE_AMT, MX_AMT, LT_AMT, FXJT_AMT, PT_DEP_AMT, PRO_DEP_AMT, PROCOUNT, FINCOUNT, INVCOUNT, BOUNS_RATIO, LOANSUM_AMT, REPAY_RAT, LEVER_RAT, OVERDUE_RAT, OVERDUE_PRO_RAT, UPDATE_DATE, CORE_MANA_AMT, CORE_WAIT_AMT, PT_WAIT_AMT, CORE_RESULT, CORE_GUARA_AMT, CORE_BOND_WAIT_AMT, PT_BOND_WAIT_AMT, BOND_RESULT FROM PALTFORMACCOUNT
2017-04-10 01:10:00.011 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.PreparedStatement] DEBUG ==> Parameters:
2017-04-10 01:10:00.013 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.ResultSet] DEBUG <== Columns: PT_NO, ACC_AMT, BOON_AMT, CUST_AMT, PRO_AMT, FEE_AMT, MX_AMT, LT_AMT, FXJT_AMT, PT_DEP_AMT, PRO_DEP_AMT, PROCOUNT, FINCOUNT, INVCOUNT, BOUNS_RATIO, LOANSUM_AMT, REPAY_RAT, LEVER_RAT, OVERDUE_RAT, OVERDUE_PRO_RAT, UPDATE_DATE, CORE_MANA_AMT, CORE_WAIT_AMT, PT_WAIT_AMT, CORE_RESULT, CORE_GUARA_AMT, CORE_BOND_WAIT_AMT, PT_BOND_WAIT_AMT, BOND_RESULT
2017-04-10 01:10:00.014 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.ResultSet] DEBUG <== Row: 006, 17115160.20, 1316359.13, 12149570.66, 3057572.01, 1638003.75, 61413.78, 0.00, 208600.00, 1316359.13, 0.00, 61841, 61841, 5, 0.00, 453419406.77, 0.68, 0.070, 0.020, 0.000, 2015-09-07 10:07:26.292735, 19534686.720, null, null, 0, 851068.580, null, null, 0
2017-04-10 01:10:00.015 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28]
4.10 cron
2017-04-10 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28]
2017-04-10 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [net.tangdi.gxseas.service.AutoRecon] INFO 數據遷移到歷史表,當前主機域名:znq133
2017-04-10 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] from current transaction
2017-04-10 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28] for iBATIS operation
2017-04-10 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.PreparedStatement] DEBUG ==> Executing: SELECT TO_CHAR(MAX(DT),"YYYY-MM-DD") FROM WORK_HOLIDAY WHERE TRASTATUS = "1"
2017-04-10 01:10:00.004 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.PreparedStatement] DEBUG ==> Parameters:
2017-04-10 01:10:00.005 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.ResultSet] DEBUG <== Columns: 1
2017-04-10 01:10:00.005 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [java.sql.ResultSet] DEBUG <== Row: 2017-04-07
2017-04-10 01:10:00.005 [org.springframework.scheduling.quartz.SchedulerFactoryBean#0_Worker-6] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@12af9e28]

可以看出這幾個SQLSession都是@12af9e28，且錯誤執行的數據就是這幾天日志查處的,證實了我的想法

解決問題

了解下mybatis 的一級緩存,select語句默認開啟,由MappedStatement的flushCache屬性控制.
那么怎么把mybatis的一級緩存關閉呢?

官網說

　1.sql級別
　2.全局FlushCache

mybatis->configuration.xml->setting標簽添加

單條關閉不適合現在的存量項目,sql太多了,排查不方便,全局吧,一運行發現mybatis3.0.6版本不支持此屬性

3.mybatis插件

全局攔截MappedStatement使flushCache=true


 

import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Plugin;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
 
import java.util.Properties;
 
/**
 * 關掉Mybatis所有查詢的一級緩存
 * Created by mumubin 2017/4/13.
 */
@Intercepts(@Signature(method = "query", type = Executor.class, args = {MappedStatement.class, Object.class,
        RowBounds.class, ResultHandler.class}))
public class FlushCacheInterceptor implements Interceptor {
 
    @Override
    public Object intercept(Invocation invocation) throws Throwable {
        MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0];
        MappedStatement copy = copyMappedStatementFlushCache(mappedStatement);
        invocation.getArgs()[0] = copy;
        return invocation.proceed();
    }
 
    /**
     * 復制MappedStatement 并設置FlushCache=true
     * @param mappedStatement
     * @return
     */
    private MappedStatement copyMappedStatementFlushCache(MappedStatement mappedStatement) {
        MappedStatement.Builder builder = new MappedStatement.Builder(mappedStatement.getConfiguration(),
                mappedStatement.getId(), mappedStatement.getSqlSource(), mappedStatement.getSqlCommandType());
        builder.resource(mappedStatement.getResource());
        builder.fetchSize(mappedStatement.getFetchSize());
        builder.statementType(mappedStatement.getStatementType());
        builder.keyGenerator(mappedStatement.getKeyGenerator());
        builder.keyProperty(mappedStatement.getKeyProperty());
        builder.timeout(mappedStatement.getTimeout());
        builder.resultMaps(mappedStatement.getResultMaps());
        builder.resultSetType(mappedStatement.getResultSetType());
        builder.cache(mappedStatement.getCache());
        builder.useCache(mappedStatement.isUseCache());
        builder.parameterMap(mappedStatement.getParameterMap());
        builder.flushCacheRequired(true);
        return builder.build();
    }
 
    @Override
    public Object plugin(Object o) {
        return Plugin.wrap(o, this);
    }
 
    @Override
    public void setProperties(Properties properties) {
    }
}

單元測試測試下吧,查緩存的日志

2017-04-14 09:00:21.495 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Creating SqlSession with JDBC Connection [com.alibaba.druid.proxy.jdbc.ConnectionProxyImpl@3541d281]
2017-04-14 09:00:21.496 [main] [java.sql.Connection] DEBUG ooo Connection Opened
2017-04-14 09:00:21.500 [main] [com.tangdi.jump.bp.service.sqlmap.support.SpringManagedTransaction] DEBUG JDBC Connection [com.alibaba.druid.proxy.jdbc.ConnectionProxyImpl@3541d281] will be managed by Spring
2017-04-14 09:00:27.437 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Registering transaction synchronization for SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf]
2017-04-14 09:00:27.442 [main] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf] for iBATIS operation
2017-04-14 09:00:37.826 [main] [java.sql.PreparedStatement] DEBUG ==> Executing: SELECT TO_CHAR(MAX(DT),"YYYY-MM-DD") FROM WORK_HOLIDAY WHERE TRASTATUS = "1" 
2017-04-14 09:00:37.826 [main] [java.sql.PreparedStatement] DEBUG ==> Parameters: 
2017-04-14 09:00:37.842 [main] [java.sql.ResultSet] DEBUG <== Columns: 1
2017-04-14 09:00:37.842 [main] [java.sql.ResultSet] DEBUG <== Row: 2017-04-05
2017-04-14 09:00:37.846 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf]
aa:2017-04-05
2017-04-14 09:00:59.856 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf] from current transaction
2017-04-14 09:00:59.856 [main] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf] for iBATIS operation
2017-04-14 09:00:59.857 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf]
bb:2017-04-05
2017-04-14 09:00:59.857 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Transaction synchronization committing SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf]
2017-04-14 09:00:59.858 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Transaction synchronization closing SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@53372fcf]

加入插件,FlushCache后的日志

2017-04-14 09:51:04.864 [main] [java.sql.Connection] DEBUG ooo Connection Opened
2017-04-14 09:51:04.867 [main] [com.tangdi.jump.bp.service.sqlmap.support.SpringManagedTransaction] DEBUG JDBC Connection [com.alibaba.druid.proxy.jdbc.ConnectionProxyImpl@7722306c] will be managed by Spring
2017-04-14 09:51:04.879 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Registering transaction synchronization for SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21]
2017-04-14 09:51:04.880 [main] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21] for iBATIS operation
2017-04-14 09:51:07.890 [main] [java.sql.PreparedStatement] DEBUG ==> Executing: SELECT TO_CHAR(MAX(DT),"YYYY-MM-DD") FROM WORK_HOLIDAY WHERE TRASTATUS = "1" 
2017-04-14 09:51:07.890 [main] [java.sql.PreparedStatement] DEBUG ==> Parameters: 
2017-04-14 09:51:07.905 [main] [java.sql.ResultSet] DEBUG <== Columns: 1
2017-04-14 09:51:07.905 [main] [java.sql.ResultSet] DEBUG <== Row: 2017-04-14
2017-04-14 09:51:07.909 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21]
aa:2017-04-14
2017-04-14 09:51:09.837 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21] from current transaction
2017-04-14 09:51:09.838 [main] [com.tangdi.jump.bp.service.sqlmap.impl.SqlMapImpl] DEBUG Opened SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21] for iBATIS operation
2017-04-14 09:51:09.839 [main] [java.sql.PreparedStatement] DEBUG ==> Executing: SELECT TO_CHAR(MAX(DT),"YYYY-MM-DD") FROM WORK_HOLIDAY WHERE TRASTATUS = "1" 
2017-04-14 09:51:09.840 [main] [java.sql.PreparedStatement] DEBUG ==> Parameters: 
2017-04-14 09:51:09.844 [main] [java.sql.ResultSet] DEBUG <== Columns: 1
2017-04-14 09:51:09.844 [main] [java.sql.ResultSet] DEBUG <== Row: 2017-04-14
2017-04-14 09:51:09.845 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21]
bb:2017-04-14
2017-04-14 09:51:09.846 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Transaction synchronization committing SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21]
2017-04-14 09:51:09.848 [main] [com.tangdi.jump.bp.service.sqlmap.support.SqlSessionUtils] DEBUG Transaction synchronization closing SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1011dc21]

ok,大功告成,bug完美解決，所以sql查詢都必須查詢數據庫了

總結

吐槽下mybatis的設計問題,ORM好好做數據庫的事情,關于緩存的事情不要做,交給redis好了,功能做就做了,但是默認開啟就不對了!!! 不管是什么開源項目,都需在保證正確性的下再考慮提示性能.在提示性能有可能引入數據錯誤的功能應默認關閉!!!!

文章版權歸作者所有，未經允許請勿轉載,若此文章存在違規行為，您可以聯系管理員刪除。

轉載請注明本文地址：http://specialneedsforspecialkids.com/yun/67016.html

相關文章

  • 記一次 Mybatis 一級緩存清理無效引起的源碼走讀

    摘要：今天對象在學習時發現對象的方法并不能清理一級緩存同一下相同查詢條件返回的結果還是舊值。測試代碼如下上網搜索網上搜索找到了相同問題并沒有人解答。例如查看官方文檔實例有一個本地緩存在執行和時被清理。要明確地關閉它獲取打算做更多的工作你可以調用。 今天對象在學習 Mybatis 時發現 org.apache.ibatis.session.SqlSession 對象的 clearCache()...

    voyagelab 評論0 收藏0

  • 記一次線上頻繁FGC的事件和解決方式

    摘要：直接顯示了一個疑似內存泄漏的問題。然后分析文件給出的信息，發現一個叫的類。文件里面說的內存泄漏的大概的意思就是說，這個類里面的存放的東西太多了，爆掉了。修改了代碼將調用的地方改成了單例。修改完線上跑了一段日子，后來也沒有出現過這樣的問題。 問題描述: ????早上去公司上班,突然就郵件一直報警,接口報異常,然后去查服務器的運行情況,發現java的cpu爆了.接著就開始排查問題 問題解決...

    Alliot 評論0 收藏0

  • 記一次驚心動魄的前端性能優化之旅

    摘要：方案未引起重視，并沒有做出相應處理。頁面中元素的布局是相對的，因此一個元素的布局發生變化，會聯動地引發其他元素的布局發生變化。這里可以使用的和來分析的性能。寫在最后性能優化是一門做減法的藝術。 歡迎一起交流 歡迎關注我的個人公眾號，不定期更新自己的工作心得。showImg(https://segmentfault.com/img/bVEk23?w=258&h=258); 正文從這里開始...

    Bryan 評論0 收藏0

發表評論

0條評論

最新活動
閱讀需要支付1元查看
<