Thanks Noveljic! I will try these
On Tue, Aug 27, 2019 at 2:39 AM Noveljic Nenad <nenad.noveljic@xxxxxxxxxxxx>
wrote:
Actually, there’s a brilliant presentation on latch internals by Andrey--
Nikolaev:
https://andreynikolaev.files.wordpress.com/2012/12/andrey_nikolaev_latch_internals_2012_for_ruoug.pdf
He provides the information on the functions which request and allocate
the latches as well as the instructions how to allocate a latch by calling
these functions. Oradebug call inside sqlplus might not work anymore, but
you can easily accomplish the same by using gdb.
There’s also code in there for reproducing row cache objects contention.
Best regards,
Nenad
*From:* oracle-l-bounce@xxxxxxxxxxxxx <oracle-l-bounce@xxxxxxxxxxxxx> *On
Behalf Of *Noveljic Nenad
*Sent:* Dienstag, 27. August 2019 07:00
*To:* krishsingh.111@xxxxxxxxx; ORACLE-L <oracle-l@xxxxxxxxxxxxx>
*Subject:* RE: How to simulate latch: cache buffers chains and latch: row
cache objects
To reproduce a latch at will and hold it for deterministic time period I
would set the breakpoint with gdb on a function participating in latch
allocation.
To get an idea which functions that might be I’d gather stack traces when
the latch event gets written into the 10046 trace files. This is something
that can be accomplished with either DTrace or gdb. I described the method
with DTrace here:
https://nenadnoveljic.com/blog/enriching-trace-with-call-stacks/
Best regards,
Nenad
@NenadNoveljic
*From:* oracle-l-bounce@xxxxxxxxxxxxx <oracle-l-bounce@xxxxxxxxxxxxx> *On
Behalf Of *kunwar singh
*Sent:* Montag, 26. August 2019 22:40
*To:* ORACLE-L <oracle-l@xxxxxxxxxxxxx>
*Subject:* How to simulate latch: cache buffers chains and latch: row
cache objects
Hi Listers,
Just an academic question.
I am trying to learn about these wait events in detail.
Can you please share what how i can reproduce it on a 12.2 or higher DB
i have a test machine with 24 cores and 12.2 DB running on it.
--
Cheers,
Kunwar
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