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about v$librarycache [message #265275]

Wed, 05 September 2007 23:50

alantany
Messages: 115
Registered: July 2007

Senior Member

Hello,all!

SQL> select namespace,pins,pinhits,reloads,invalidations from v$librarycache order by namespace;

NAMESPACE PINS PINHITS RELOADS INVALIDATIONS
--------------- ---------- ---------- ---------- -------------
SQL AREA 526476359 3817291641 24827833 244755

I noticed that the PINS<>PINHITS+RELOADS+INVALIDATIONS
even more,the PINHITS is much larger then the PIN
Why?
Regards!
Alan

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Re: about v$librarycache [message #265277 is a reply to message #265275]

Wed, 05 September 2007 23:58

Arju
Messages: 1554
Registered: June 2007
Location: Dhaka,Bangladesh. Mobile:...

Senior Member

PINS ==Number of times a PIN was requested for objects of this namespace

PINHITS==Number of times all of the metadata pieces of the library object were found in memory

INVALIDATIONS =The total number of times objects in this namespace were marked invalid because a dependent object was modified

SQL> select namespace,pins,pinhits,reloads,invalidations from v$librarycache order by namespace;

NAMESPACE             PINS    PINHITS    RELOADS INVALIDATIONS
--------------- ---------- ---------- ---------- -------------
BODY                274717     272505       1731             0
CLUSTER               8694       8527        124             0
INDEX                 6747       4612        672             0
JAVA DATA                0          0          0             0
JAVA RESOURCE            0          0          0             0
JAVA SOURCE              0          0          0             0
OBJECT                   0          0          0             0
PIPE                     0          0          0             0
SQL AREA           1402052    1338985      29501           571
TABLE/PROCEDURE     666745     597096      27741             0
TRIGGER              17132      16605        289             0

11 rows selected.

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Re: about v$librarycache [message #265278 is a reply to message #265275]

Thu, 06 September 2007 00:00

Arju
Messages: 1554
Registered: June 2007
Location: Dhaka,Bangladesh. Mobile:...

Senior Member

I noticed that the PINS<>PINHITS+RELOADS+INVALIDATIONS

Will it be same?
Have a look at,

http://download.oracle.com/docs/cd/B19306_01/server.102/b14211/memory.htm#sthref578

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Re: about v$librarycache [message #265321 is a reply to message #265278]

Thu, 06 September 2007 02:19

alantany
Messages: 115
Registered: July 2007

Senior Member

Arju wrote on Thu, 06 September 2007 00:00

I noticed that the PINS<>PINHITS+RELOADS+INVALIDATIONS

Will it be same?
Have a look at,

http://download.oracle.com/docs/cd/B19306_01/server.102/b14211/memory.htm#sthref578

Thanks,Arju!
But I still confuzed with PINS and PINHITS?
I think if a pin was get successfully,PINHITS will plus 1,otherwise,reloads will plus 1,please kindly correct me.
Regards!
Alan

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Re: about v$librarycache [message #265326 is a reply to message #265321]

Thu, 06 September 2007 02:24

Michel Cadot
Messages: 68737
Registered: March 2007
Location: Saint-Maur, France, https...

Senior Member
Account Moderator

The first load is not a reload, for instance.

Regards
Michel

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Re: about v$librarycache [message #265355 is a reply to message #265326]

Thu, 06 September 2007 03:05

alantany
Messages: 115
Registered: July 2007

Senior Member

Michel Cadot wrote on Thu, 06 September 2007 02:24

The first load is not a reload, for instance.

Regards
Michel

Thanks,Michel!
But of my case,the reloads is much larger than PINs.

NAMESPACE PINS PINHITS RELOADS INVALIDATIONS
--------------- ---------- ---------- ---------- -------------
SQL AREA [B]526476359 3817291641[/B] 24827833 244755

Why？
Regards!
Alan

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Re: about v$librarycache [message #265366 is a reply to message #265275]

Thu, 06 September 2007 03:26

Arju
Messages: 1554
Registered: June 2007
Location: Dhaka,Bangladesh. Mobile:...

Senior Member

Quote:

But of my case,the reloads is much larger than PINs.

NAMESPACE PINS PINHITS RELOADS INVALIDATIONS
--------------- ---------- ---------- ---------- -------------
SQL AREA 526476359 3817291641 24827833 244755

I don't see.
In your example RELOAD=24827833
and PINS=526476359

Which is larger?

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Re: about v$librarycache [message #265382 is a reply to message #265366]

Thu, 06 September 2007 04:08

Michel Cadot
Messages: 68737
Registered: March 2007
Location: Saint-Maur, France, https...

Senior Member
Account Moderator

This is the kind of errors that can be made with bad formatting. Mad

Regards
Michel

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Re: about v$librarycache [message #265390 is a reply to message #265366]

Thu, 06 September 2007 04:21

alantany
Messages: 115
Registered: July 2007

Senior Member

Arju wrote on Thu, 06 September 2007 03:26

Quote:

I don't see.
In your example RELOAD=24827833
and PINS=526476359

Which is larger?

I am very sorry for my stupid.
I just want to say here the PINHITS is much large than the PINS,I think when there is a pin,the PIN will plus 1,if it success,PINHITS plus 1,so PINs will always >= PINHITs,YES?
But ,here,the PINS=552647639 and PINHITS=3817291641
Why?
Regards!
Alan

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Re: about v$librarycache [message #265425 is a reply to message #265390]

Thu, 06 September 2007 05:28

Michel Cadot
Messages: 68737
Registered: March 2007
Location: Saint-Maur, France, https...

Senior Member
Account Moderator

Because counters are 4 bytes and then yours wrap around.

Regards
Michel

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Re: about v$librarycache [message #265508 is a reply to message #265326]

Thu, 06 September 2007 08:36

alantany
Messages: 115
Registered: July 2007

Senior Member

Thanks!Michel:
Yes，I think it is the answer!
But could you kindly give a explain on my first qustion：
Does PINs=PINHITs+RELOADS+ INVALIDATIONS？
If　not,what the relationships of them?
Regards!
Alan

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