Lab 128 on RAC environment

[mbe...@gmail.com]

I am using lab 128 near the two year that is great oracle monitoring
tool. Its very cheap and good solution compared with the compatitors.

I want to ask some questions. While I am using 1.5.9.0 on RAC
environment I am facing high cpu utilization also receive oracle rac
related problems so I chose older 1.5.8.2 version on our RAC
environment.

Is there any adea ? What was the this problems root ?

[Sergei - Lab128 team]

Hi,

Did you try Lab128 current version 1.5.9.2? Which Oracle version you
use?
You can use Lab128 to find this cpu-expensive query: in SQL Explorer
(main menu: View | SQL Explorer) select 15-20 minute interval, sort
tabular data by "CPU Time" and uncheck "Exclude Lab128" check box.
Then find the top query that is used by lab128 - sql text starts with
--lab128. Can you find that and post the query?

Based on my experience, this should be a query using v$session (gv
$session in RAC). It pulls data from gv$session and joins with v$sql.
This is a difference between 1.5.8 and 1.5.9. x. The only reason for
this join was to get PLAN_HASH_VALUE which is missing in v$session
view. This works well in the single instance, in RAC this join was
causing problems. In the upcoming version, we decided to remove the
join and cache PLAN_HASH_VALUE in the application, then joining that
data inside Lab128. This fixed this problem. If you would like to run
beta version, I will explain to get it.

Regards,
Sergei