Tracing PL/SQL subprogram calls with parameters values [Dynamic tracing]

The purpose of this blog post is demonstrate again the power of Linux dynamic tracing/instrumentation tools.

In my last blog post Enhancing DBMS_OUTPUT using systemtap i showed how we can track  the parameter values passed to “dbms_output.put_line” routine using systemtap.That was a very simple example because we already know the type of the arguments passed (a simple VARCHAR2) and also because there is only ONE parameter.

Tracking PL/SQL routine calls arguments using dynamic tracing utility like perf or systemtap can become quite complex depending on many things like :

  • Argument types
  • Argument number
  • Argument passed  By Value/By reference
  • Subprograms type (nested/package/standalone subprogram)
  • Optimization level (ex: inlining of call of procedure)

Time for the serious stuff  with dynamic tracing tool PERF ! 

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Geeky PL/SQL tracer/profiler : Another step

This is my second post under the theme of how to extend our capabilities to trace and profile PL/SQL code.This time motivated by a comment from Luca Canali on my previous post  :

So based on my previous work on geeky PL/SQL tracer let’s see how we can obtain a geeky PL/SQL on-CPU Flame Graph !

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Geeky PL/SQL tracer/profiler : First step

This blog post is about how to extend our capabilities to trace and profile PL/SQL code.It’s primarily motivated by few tweets from Franck Pachot and of course because it’s FUN !

Capture 02

Capture 01

So in the first part of this series we are going to answer to this questions : Can we map those underling function to the source PL/SQL object and line number ? Can we obtain a full trace ? Of course yes otherwise there will be no blog post :p

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POUG : Memory access tracing slides

You know POUG ? Of course you know POUG ! This is one of the best  Oracle conference out there ! Great peoples ! Great Speakers ! Great Place ! Awesome ambiance !!!

Last week i was honored to be there ! It was a pleasure to meet many other Oracle geeks and to participate to this great event !

Poug_day

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So as promised here is my presentation (My first public speak by the way)  on slide share : Just click here !

Many thanks for all the POUG Team for this great adventure ! Don’t miss POUG18 !!!!

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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