"enq: RO - fast object reuse" due to truncate temp table

Dear Guru's,
DB_VERSION=10.2.0.4
OS_VERSION=64-bit Windows 2008 R2
This morning one of our Production databases peformance was
I have collected AWR information during that time and found "*enq: RO - fast object reuse*" followed by "CPU time".
Also as per the ADDM :
RECOMMENDATION 2: SQL Tuning, 48% benefit (1603 seconds)
      ACTION: Investigate the SQL statement with SQL_ID "62fs5g3mqhd4b" for
         possible performance improvements.
         RELEVANT OBJECT: SQL statement with SQL_ID 62fs5g3mqhd4b and
         PLAN_HASH 1328042859
         TRUNCATE TABLE Transaction_Tmp
      RATIONALE: Waiting for event "enq: RO - fast object reuse" in wait class
         "Application" accounted for 98% of the database time spent in
         processing the SQL statement with SQL_ID "62fs5g3mqhd4b"
As per the Bug 8544896 - Waits for "enq: RO - fast object reuse" with high DBWR CPU [ID 8544896.8] ,
Workaround:
Flush the buffer cache before truncating
OR
set dbfast_obj_truncate = FALSE
However they have also mentioned for applying the patch to fix this issue ex:10.2.0.4 Patch 27 on Windows Platforms. But there exist the list of Patches i mean it's so confusing. I do not see anything that suits with my OS i.e. Windows 2008 64-bit :-(
I have following concerns :
Q1. Also according to "'enq: RO - fast object reuse' contention when gathering schema/table statistics in parallel [ID 762085.1]" , Both workarounds could have an impact on the database performance. Instead, it is recommended applying the corresponding patch
I mean shall i ignore this since i have encountered 'enq: RO - fast object reuse' during truncating the Temp Table and not while gathering statistics.
Q2. Or shall i try this workaround and observe the database performance ? ( which i am planning to perform currently)
Q3. Which is the correct Patch Number for the same? Since there are many Patches listed.
Thanks in advance

A MetaLink Research for the term “kcbo_service_ockpt” leads to Bug 7376934, which is a duplicate of Bug 7385253 – DBWR IS CONSUMING HIGH CPU.
Patch 7385253 is available for Linux x86_64, HP-UX, Solaris, AIX.
Reference:
MetaLink Note 762085.1 – Subject: ‘enq: RO – fast object reuse’ contention when gathering schema/table statistics in parallel

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Hi,
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Is this a Duplicate Post ? See truncate 1000 tables

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Hi all,
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You are trying : trucate
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Team,
We have a table of size 550gigs in size and we truncated the table , truncated sucessfully but space is not released in os level, what action we can take to release the space and this table has only one row and contains the binary data.
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ERROR at line 1:
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LINE 49 is the line corresponding to enable constraint statement.
Edited by: kumar73 on 3 Sep, 2012 11:44 PM

It is such a pity that a user having 321 posts till date is unaware of basics of Posting a Question.
1. You need to provide us with your Oracle version
select * from v$version;2. You need to understand and get accustomed to using tags before and after Code or SQL's for better readability.
3. You need to provide us with the Table Structure and the Constraints Definition.
There are many things that looks like Bad Coding practices:
<font face="Times New Roman" size=2>
1. Avoid RBAR (Loops).
2. Implement Bulk Collect.
3. Why do you need to disable the constraints before truncating? Are you kind of handling the Referential Integrity Constraints?
4. Duplicate checking of Disabled Constraints.
5. When the procedure is being executed at Production Environment, are you going to Monitor the DBMS_OUTPUT? Why not Log the Statements into a LOG Table?
6. Why use a TableCount variable? Would the TableCount Variable be not equal to the Number of Records returned by Cursor C?
7. What is the need to use a NULL statement after every Execute Immediate?
8. What is the Need to surround each execute Immediate with Begin .. End block?
9. Where is your Exception handling Block? Forgot to write?
</font>
What has been your effort in finding which Constraint/Table is causing you the trouble?

"enq: RO - fast object reuse" due to truncate temp table

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