"ARCH wait on SENDREQ" This wait event monitors the amount of time spent by all archiver processes to write the received redo to disk as well as open and close the remote archived redo logs. db version and os version?
PHP code:Applies to: Oracle Server - Enterprise Edition - Version: 9.2.0.6 This problem can occur on any platform. Symptoms High ARCH wait on SENDREQ wait events found in statspack report. Cause High ARCH wait on SENDREQ wait events found in statspack report. "ARCH wait on SENDREQ" -- This wait event monitors the amount of time spent by all archiver processes to write the received redo data to disk as well as open and close the remote archived redo log files.This wait events can lead to a slow performance. 1)It means that there is a slow network between primary and standby database. 2)It also means that there is a chance of slow performance on disk where remote archiving is happening. . Solution To implement the solution, please execute the following steps: 1.Please get in touch with your network admin and check the network response. 2.If the remote destination is slow and archiver is taking longer to archive to that destination, then the user needs to allocate more redo log groups so that there is a logfile available for a logswitch to switch into, and not wait for the archiver to finish archiving to the destination. 3.One more workaround you can use is to set below parameter in primary site: _LOG_ARCHIVE_CALLOUT='LOCAL_FIRST=TRUE'
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Data Guard Wait Events
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dataguard相关等待事件