Getting Latch holder info out of the state objects in SGA memory

Updated 12/05/2017

It will be great to have a tool that will extract latch holder information directly from state objects  stored inside the SGA. This way we will reduce the overhead when troubleshooting latch contention an beside that it’s also cool !!

This may sound difficult ! How to proceed ? and the answer is …. Memory reference tracing !

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Improved remote session debugging (DBMS_DEBUG_JDWP)

“Improving the PL/SQL Debugger:

In prior releases, it was necessary to change the application to include calls to start and stop debugging. With this improvement, one database session can start debugging, and stop debugging a different session.”

“With these improvements, if a problem occurs in a long running test or in a production environment, it is possible to investigate the problem from another session.” Oracle Database 12c Release 2 (12.2) New Features

Let’s take a closer look :

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Workaround for systemtap issue : Oracle Tracing [registration error (rc 0) !]

This is my third blog post about an issue that we may encounter with uprobes and the recent kernel/oracle version.

As the name of this article suggest i will show here how we can put a probe point on oracle functions using systemtap based on the workaround that i described previously.

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Workaround for Linux Perf Probes issue for Oracle Tracing

As explained in my previous post there is some issues with uprobes and the recent kernel/oracle version.Based on the workaround that i described i will show in  this short blog post how we can put a probe point on oracle function using Linux Perf. Sadly i haven’t figured out a way to do that using systemtap (Special thanks to Frank Ch. Eigler for his help)

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