Re: Segments by Logical Reads-AWR
- From: Mohamed Houri <mohamed.houri@xxxxxxxxx>
- To: Jonathan Lewis <jonathan@xxxxxxxxxxxxxxxxxx>
- Date: Fri, 19 Sep 2014 11:58:11 +0200
Jonathan,
Yes. You are right. I learnt something new. Thanks for that.
There are several inserts into tables (which when checked after your e-mail
reveal to be *GTT ON COMMIT DELETE ROWS*) that appear in
(a) SQL Ordered by Reads
(b) SQL Ordered by Physical Read (UnOptimized))
I was only wondering why this TRANSIENT MISSING name object has been
reported in
(a) Segments by Logical Read
and not in
(b) Segment by Physical Read or Segment by UnOptimized Reads
As far as they appear in the equivalent SQL Ordered by Reads and SQL
Ordered by Physical Read (UnOptimized)) parts
It might be only a question of *”Something has to be in the top of
Segments by Reads.." *competition where other segments win.
Best regards
Mohamed Houri
2014-09-18 16:22 GMT+02:00 Jonathan Lewis <jonathan@xxxxxxxxxxxxxxxxxx>:
>
> One possibility is that it's the statistics left from a freed
> instantiation of a global temporary table - i.e. when the session has
> committed on an "on commit release" GTT or truncated on an "on commit
> preserve" GTT. The 4228608 identifies the first block of the segment - in
> your example subtract power(2,22) from the value to get the block number in
> the first file of the temp tablespace.
>
>
> Regards
> Jonathan Lewis
> http://jonathanlewis.wordpress.com
> @jloracle
> ------------------------------
> *From:* Mohamed Houri [mohamed.houri@xxxxxxxxx]
> *Sent:* 18 September 2014 14:50
> *To:* Jonathan Lewis
> *Cc:* ORACLE-L
> *Subject:* Re: Segments by Logical Reads-AWR
>
> Hi Jonathan,
>
> It is a temporary tablespace (they are very using a clean naming
> standard with *_T* to signal that it is a temporary tablespace)
>
> Best regards
>
> Mohamed Houri
>
> 2014-09-18 15:39 GMT+02:00 Jonathan Lewis <jonathan@xxxxxxxxxxxxxxxxxx>:
>
>>
>>
>> Is the tablespace whose name you've obfuscated a temporary tablespace or
>> a permanent tablespace ?
>>
>>
>>
>>
>> Regards
>> Jonathan Lewis
>> http://jonathanlewis.wordpress.com
>> @jloracle
>> ------------------------------
>> *From:* oracle-l-bounce@xxxxxxxxxxxxx [oracle-l-bounce@xxxxxxxxxxxxx] on
>> behalf of Mohamed Houri [mohamed.houri@xxxxxxxxx]
>> *Sent:* 18 September 2014 14:21
>> *To:* ORACLE-L
>> *Subject:* Segments by Logical Reads-AWR
>>
>> Dear List,
>>
>>
>> Can someone tell me what could be this TRANSIENT object name that
>> appears in the *Segments by Logical Reads* and *Segments by DB Blocks
>> Changes* parts of a 60 minutes AWR report?
>>
>>
>> *Segments by Logical Reads*
>>
>> - Total Logical Reads: 212,371,958
>> - Captured Segments account for 76.3% of Total
>>
>> *Owner*
>>
>> *Tablespace Name*
>>
>> *Object Name*
>>
>> *Subobject Name*
>>
>> *Obj. Type*
>>
>> *Logical Reads*
>>
>> *%Total*
>>
>> ** MISSING **
>>
>> XXX_T
>>
>> ** TRANSIENT: 4228608
>>
>> ** MISSING **
>>
>> UNDEFINED
>>
>> 19,557,632
>>
>> 9.21
>>
>>
>>
>> *Segments by DB Blocks Changes*
>>
>> - % of Capture shows % of DB Block Changes for each top segment
>> compared
>> - with total DB Block Changes for all segments captured by the
>> Snapshot
>>
>> *Owner*
>>
>> *Tablespace Name*
>>
>> *Object Name*
>>
>> *Subobject Name*
>>
>> *Obj. Type*
>>
>> *DB Block Changes*
>>
>> *% of Capture*
>>
>> ** MISSING **
>>
>> XXX_T
>>
>> ** TRANSIENT: 4228608
>>
>> ** MISSING **
>>
>> UNDEFINED
>>
>> 5,966,256
>>
>> 13.63
>>
>>
>>
>> There is a note in MyOracle support which seems close to this subject but
>> does not fit exactly with what I have been told by the developers about
>> their application.
>>
>>
>> Bug 8811401 <https://support.oracle.com/rs?type=bug&id=8811401> (Note
>> 8811401.8 <https://support.oracle.com/rs?type=doc&id=8811401.8>)
>>
>>
>> Thanks in advance
>>
>> --
>>
>> Houri Mohamed
>>
>> Oracle DBA-Developer-Performance & Tuning
>>
>> Member of Oraworld-team <http://www.oraworld-team.com/>
>>
>> Visit My - Blog <http://www.hourim.wordpress.com/>
>>
>> Let's Connect -
>> <http://fr.linkedin.com/pub/mohamed-houri/11/329/857/>*Linkedin
>> Profile <http://fr.linkedin.com/pub/mohamed-houri/11/329/857/>*
>>
>> My Twitter <https://twitter.com/MohamedHouri> - MohamedHouri
>> <https://twitter.com/MohamedHouri>
>>
>>
>
>
> --
>
> Houri Mohamed
>
> Oracle DBA-Developer-Performance & Tuning
>
> Member of Oraworld-team <http://www.oraworld-team.com/>
>
> Visit My - Blog <http://www.hourim.wordpress.com/>
>
> Let's Connect -
> <http://fr.linkedin.com/pub/mohamed-houri/11/329/857/>*Linkedin
> Profile <http://fr.linkedin.com/pub/mohamed-houri/11/329/857/>*
>
> My Twitter <https://twitter.com/MohamedHouri> - MohamedHouri
> <https://twitter.com/MohamedHouri>
>
>
--
Houri Mohamed
Oracle DBA-Developer-Performance & Tuning
Member of Oraworld-team <http://www.oraworld-team.com/>
Visit My - Blog <http://www.hourim.wordpress.com/>
Let's Connect -
<http://fr.linkedin.com/pub/mohamed-houri/11/329/857/>*Linkedin
Profile <http://fr.linkedin.com/pub/mohamed-houri/11/329/857/>*
My Twitter <https://twitter.com/MohamedHouri> - MohamedHouri
<https://twitter.com/MohamedHouri>
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