1 定义理解
关于Oracle GoldenGate （简称OGG）的 Lag at Chkpt和Time Since Chkpt的理解，前提需要理解OGG的每个进程都有它自己的checkpoint file。每当一个进程看到在事务的commit时，检查点文件中就将产生一个检查点。OGG的恢复进程总是以检查点作为起点。而OGG是通过监控的checkpoint和Lag at Chkpt和Time Since Chkpt这2个指标来衡量数据同步延迟时效的。
2 问题出现
最近新上一批OGG数据抽取和投递服务器，原采集服务器也是按照相同的操作步骤部署在目标服务器上并没有出现今日的问题。今日运维在测试环境发现新上的一批采集器并不能处理相应的任务，查看日志发现采集器打印出来如下错误信息：
- 错误信息一
Error1- 错误信息二
Error2- 错误信息三
Error33 排查思路和解决方案
根据图一、图二这些错误日志信息，能看到的只是知道哪些文件出现了错误以及出现错误的排查方向，因此根据运维同事提供的日志信息并向运维同事索要了相应的日志文件来排查问题出现的具体原因。
通过解析同事提供的日志文件，排查出来OGG的某个参数配置文件（*.prm）中含有#的表并不能进行解析成树。根据图二找到问题的所在，提供解决方案：https://stackoverflow.com/questions/33328157/antlr4-token-recognition-error-at
根据图三排查出来某些任务进程，在这里找到了答案：https://blog.csdn.net/xiangsir/article/details/9883929
由于在OGG中执行命令GGSCI>info all 显示lag不一定真的有lag，这个lag 有可能是redo时间和系统时间有差距导致的。
感谢同事以及领导在排查问题提供很多意见，让排查问题的范围缩小，降低排查难度。
4 其他
附录：OGG一些常见的问题与错误及其解答
代码语言：javascript复制Note: 966211.1 How To Resync A Single Table With Minimum Impact To Other Tables' Replication?
Note: 966227.1 Troubleshooting TCP/IP Errors In Open Systems
Note: 972954.1 What Causes The 'Bad Column Index(xxxx)' Error In Replicat?
Note: 987379.1 How to recover from Extract ERROR 180 encountered commit SCN that is not greater than the highest SCN already processed
Note: 1112506.1 GoldenGate Extract Abends with "Unable to lock file" Error For Trail File
Note: 1124403.1 When Replicat is Running but Not Applying Records
Note: 1138409.1 EXTRACT / REPLICAT CHECKPOINT RBA IS LARGER THAN LOCAL TRAILFILE SIZE, AFTER SERVER CRASH
Note: 1163073.1 When using rmthost with timeout option, there are orphaned data collector processes on target system
Note: 1266389.1 Oracle GoldenGate and compressed tables
Note: 1270168.1 OGG-01028 Compression Not Supported - when extract processes regular and cluster tables
Note: 1276538.1 Replicat abending with missing key cols
Note: 1280584.1 Where To Find The List Of Supported And Unsupported Oracle Data Types for GoldenGate
Note: 1288562.1 GG Data Pumps Error With OGG-01031 When Upgrading the Target Side
Note: 957112.1 Encountered SCN That Is Not Greater Than The Highest SCN Already Processed
Note: 1271578.1 How to Handle Tables without Primary Keys or Unique Indexes with Oracle GoldenGate
Note: 957053.1 Recovering From a GG Pump Process Abending With An Incompatible Record Error
Note: 968622.1 Does GoldenGate Support Tables With An UNUSED Column?
Note: 968614.1 Why Does GoldenGate Report The Lag Is Unknown or a Timestamp Mismatch?
Note: 968769.1 GoldenGate Errors That Occur In Teradata Extract Setting
Note: 1163073.1 When using rmthost with timeout option, there are orphaned data collector processes on target system
Note: 964709.1 How To Handle Oracle DDLs (add/drop/resize a Column) 22 19 1
Note: 1300076.1 Usage and considerations for allocation of ports and DYNAMICPORTLIST
Note: 1232303.1 mount options to use when configuring GoldenGate to run on NFS mounted file system
Note: 1298548.1 Extract not accepting CACHESIZE settings
Note: 1300197.1 Logger not logging cobol transactions for GGSLIB with non default AUDCFG location
Note: 1273285.1 How To Troubleshoot Oracle Redo Log Reading Extract Slow Performance Issue Note: 965356.1 GGS Error 150: No Dynamic Ports Available
Note: 1199561.1 Characterset Conversion: Error 160 Bad column length
Note: 1159684.1 Extract abends,mss: missing trailing blocks, unable to queue I/O, I/O beyond file size
Note: 1292874.1 GoldenGate Extract Abends on Startup with Error OGG-01088 Realloc xxx Bytes Failed.
Note: 1271522.1 Oracle GoldenGate (OGG) 11.1>>> .1>>> .0 and Transparent Data Encryption (TDE)
Note: 965270.1 How does the Manager Allocate TCPIP Ports?
Note: 1195995.1 Implementing GoldenGate for DataGuard fail overs
Note: 965373.1 Installing And Configuring GoldenGate In An Oracle RAC Environment
Note: 1276058.1 Oracle GoldenGate Best Practices: Instantiation from an Oracle Source Database
Note: 971264.1 How To Upgrade GGS Objects In A DDL Replication Environment Note 957112.1 Encountered SCN That Is Not Greater Than The Highest SCN Already Processed
Note 969550.1 Using SCN To Do The Initial Load From Oracle To Oracle Database
Note 966211.1 How To Resync A Single Table With Minimum Impact To Other Tables' Replication?
Note 1235986.1 Does Oracle Goldengate extract support distributed transactions?
Note 966227.1 Troubleshooting TCP/IP Errors In Open Systems
Note 972954.1 What Causes The 'Bad Column Index(xxxx)'; Error In Replicat?
Note 987379.1 How to recover from Extract ERROR 180 encountered commit SCN that is not greater than the highest SCN already processed (GG Version 10)
Note 1112325.1 Deploying OGG to Achieve Operational Reporting for Oracle E-Business Suite
Note 1112506.1 GoldenGate Extract Abends with "Unable to lock file" Error For Trail File
Note 1120793.1 How to Get More Information than from Just a Trace on LINUX Boxes for GoldenGate
Note 1124403.1 When Replicat is Running but Not Applying Records
Note 1138409.1 EXTRACT / REPLICAT CHECKPOINT RBA IS LARGER THAN LOCAL TRAILFILE SIZE, AFTER SERVER CRASH
Note 1163073.1 When using rmthost with timeout option, there are orphaned data collector processes on target system
Note 1266389.1 Oracle GoldenGate and compressed tables
Note 1270168.1 OGG-01028 Compression Not Supported - when extract processes regular and cluster tables
Note 1272645.1 Maintaining the OGG Marker table
Note 1276058.1 Oracle GoldenGate Best Practices: Instantiation from an Oracle Source Database
Note 1276538.1 Replicat abending with missing key cols
Note 1280584.1 Where To Find The List Of Supported And Unsupported Oracle Data Types for GoldenGate
Note 1288562.1 GG Data Pumps Error With OGG-01031 When Upgrading the Target Side我正在参与2023腾讯技术创作特训营第三期有奖征文，组队打卡瓜分大奖！
