您的位置：首页 > 其它

How does LGWR/LNS process work in 10gR2 using LGWR ASYNC (文档 ID 1057898.1)

2014-05-18 09:32 567 查看

APPLIES TO:

Oracle Server - Enterprise Edition - Version: 10.2.0.1 to 10.2.0.5 - Release: 10.2 to 10.2

Information in this document applies to any platform.

GOAL

This Note describes the behavior of LGWR/LNS process in 10gR2 using LGWR ASYNC-mode.

SOLUTION

In Oracle Database 10g Release 2, the new LGWR ASYNC behavior has changed since the LGWR process doesn't writes to the ASYNC buffer anymore. When the LGWR has completed writing to the online log, the LNSn process reads from the online redo log and ships the
redo to the RFS-process on the standby database. If LGWR switches into a new online log file before the LNSn process has completed, then LNSn continues to remotely archive its current log file. If LGWR once again switches to a new online redo log file while
the LNSn process is still on the original log file, then the ARCH process remotely archives the log file that the LNSn process has not yet begun to archive. Once LNSn has completed archiving its original log file, it begins archiving the current log file for
LGWR.

When the LGWR is switching to the original online redo log and the LNS process

is still not ready to archive the original online redo log, the LNS will be stop to archive this online redo log. At this time the online redo log is already locally archived. The standby database will recognize a GAP since the content from the original online
redo log is not completely received there. The GAPs will be resolved automaticyll by the ARCH process.

This new LGWR ASYNC behavior in 10gR2 eliminates the potential to stall the production database.

REFERENCES

NOTE:387174.1 - MAA - Data Guard Redo Transport and Network Best Practices

内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理

标签： lgwr async dataguard

相关文章推荐

新的分享

章节导航