Re: Is enq: TX - row lock contention a wait or syscall

  • From: Cary Millsap <cary.millsap@xxxxxxxxxxxx>
  • To: Stefan Koehler <contact@xxxxxxxx>
  • Date: Wed, 22 Jan 2020 08:45:05 -0600

I like this: you can clearly see the three-second-duration semtimedop()
calls.


Cary Millsap
Method R Corporation
Author of *Optimizing Oracle Performance <http://amzn.to/OM0q75>*
and *The Method R Guide to Mastering Oracle Trace Data, 3rd edition
<https://amzn.to/2IhhCG6+-+Millsap+2019.+Mastering+Oracle+Trace+Data+3ed>*



On Tue, Jan 21, 2020 at 1:18 AM Stefan Koehler <contact@xxxxxxxx> wrote:

Hello Kunwar,
as all others already replied: Yes, the wait event "enq: TX - row lock
contention" instruments a wait on syscall semtimedop() in the background.

On my website you can find a simple example how the locking /
synchronization works:
http://www.soocs.de/public/research/190513_semaphore_sync.txt

Best Regards
Stefan Koehler

Independent Oracle performance consultant and researcher
Website: http://www.soocs.de
Twitter: @OracleSK

kunwar singh <krishsingh.111@xxxxxxxxx> hat am 20. Januar 2020 um 15:29
geschrieben:

Hi Listers,
I am reading the below blog:


http://carymillsap.blogspot.com/2009/02/dang-it-people-theyre-syscalls-not.html


So i have one basic question. Is  enq: TX - row lock contention also a
syscall then or am i simplifying it too much?

--
Cheers,
Kunwar
--
//www.freelists.org/webpage/oracle-l



Other related posts:

  1. Home
  2. oracle-l
  3. Archive
  4. 01-2020