Inside RAC

1 © 2006 Julian Dyke

InsideRAC

Julian DykeIndependent Consultant

Web Version

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Agenda

Introduction to RAC

Memory Structures

The Buffer Cache

Global Cache Services

The Library Cache

Global Enqueue Services

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Introductionto

RAC

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What is RAC? Multiple instances running on separate servers (nodes)

Single database on shared storage accessible to all nodes

Instances exchange information over an interconnect network

Node 1

Instance 1

Node 2

Instance 2Interconnect

Shared Storage

LocalDisk

LocalDisk

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Architecture

Instance 1

Node 1

Instance 2

Node 2

SharedStorage

Storage Network

Private Network(Interconnect)

Public Network

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Some Definitions Resource

Object to which access must be controlled at instance level

Enqueue Memory structure that serializes access to a resource

Global Resources Object to which access must be controlled at cluster level

Global Enqueue Locks and enqueues which need to be consistent between

all instances

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Some Definitions... Global Resource Directory (GRD)

Records current state and owner of each resource Contains convert and write queues Distributed across all instances in cluster Maintained by GCS and GES

Global Cache Services (GCS) Implements cache coherency for database Coordinates access to database blocks for instances

Global Enqueue Services (GES) Controls access to other resources (locks) including

library cache and dictionary cache Performs deadlock detection

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Instance 2Instance 1

Background Processes

DIAG

LMON

LCK

LMD

LMS

LGWR

SMONPMON

CKPT

ARCH

DIAG

LMON

LCK

LMD

LMS

CKPT

ARCH

LGWR

PMON

DBWR

SMON

DBWR

Redo Logs

DatafilesControlfiles

Redo Logs

SGAUGASGA UGA

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Background Processes LMSn

Global Cache Service Process

Manage requests for data access across cluster

Up to 20 in Oracle 10.1 LMS0-LMS9 LMSa-LMSj

Up to 36 in Oracle 10.2 LMS0-LMS9 LMSa-LMSz

In Oracle 10.1 and above, number of GCS server processes can be configured using gcs_server_processes parameter

Default value is 1 (single CPU system)

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Background Processes LCK0

Instance Enqueue Process

Manages instance resource requests cross-instance call operations

Assists LMS processes

Formerly known as lock process

In 9.0.1 and below, number of lock processes may be configurable using _gc_lck_procs parameter

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Background Processes LMD0

Global Enqueue Service Daemon

Manages requests for global enqueues Updates status of enqueues when granted to / revoked

from an instance

One LMD0 process per instance

In 8.1.7 and below number of lock daemons may be configurable using _lm_dlmd_processes parameter

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Background Processes LMON

Global Enqueue Service Monitor

One LMON process per instance

Monitors cluster to maintain global enqueues and resources

Manages instance and process expirations recovery processing for cluster enqueues

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Background Processes DIAG - Diagnosibility Process

Collects diagnostic data in the event of a failure

Creates subdirectories in BACKGROUND_DUMP_DEST directory

In Oracle 9.0.1 and above can be disabled using _diag_daemon parameter

Do not try this on a production system

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Fixed Tables Memory structures externalized in X$ tables Instance specific Underlying structures for dynamic performance views Can contain

Structures accessed directly from executable X$KSLLD => V$LATCHNAME X$KSUSD => V$STATNAME

Structures accessed directly from SGA X$KSUSE => V$SESSION X$KSUPR => V$PROCESS

Executable and/or SGA structures joined in PGA X$KQLFXPL => V$SQL_PLAN X$KGLOB => V$SQL, V$SQL_AREA

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Dynamic Performance Views In a RAC environment each V$ view has an equivalent GV$

view GV$ view includes INST_ID column. For example V$SGA

NAME VARCHAR2(20)

VALUE NUMBER

GV$SGAINST_ID NUMBERNAME VARCHAR2(20)VALUE NUMBER

In Oracle 9.2 and below PARALLEL_MIN_SERVERS must be >= number of hosts to use GV$ views

In Oracle 10.1 and above PZnn background processes are used to return data on remote hosts e.g. PZ99

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CATCLUST.SQL Some additional views/synonyms are created for RAC

databases using $ORACLE_HOME/rdbms/admin/catclust.sql

Synonym Name View NameV$GES_CONVERT_LOCAL V$DLM_CONVERT_LOCALV$GES_CONVERT_REMOTE V$DLM_CONVERT_REMOTEV$GES_LATCH V$DLM_LATCHV$GES_RESOURCE V$DLM_RESSV$GES_STATISTICS V$DLM_MISCV$GES_TRAFFIC_CONTROLLER V$DLM_TRAFFIC_CONTROLLER

GV$GES_CONVERT_LOCAL GV$DLM_CONVERT_LOCAL

GV$GES_CONVERT_REMOTE GV$DLM_CONVERT_REMOTE

GV$GES_LATCH GV$DLM_LATCH

GV$GES_RESOURCE GV$DLM_RESS

GV$GES_STATISTICS GV$DLM_MISC

GV$GES_TRAFFIC_CONTROLLER GV$DLM_TRAFFIC_CONTROLLER

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ORADEBUG ORADEBUG includes LKDEBUG

Must be run by user with SYSDBA privilege

SQL> ORADEBUG LKDEBUG HELP

Usage:lkdebug [options] -l [r|p] <enqueue pointer> Enqueue Object -r <resource pointer> Resource Object -b <gcs shadow pointer> GCS shadow Object -p <process id> client pid -P <process pointer> Process Object -O <i1> <i2> <types> Oracle Format resname -a <res/lock/proc> all <res/lock/proc> pointer -A <res/lock/proc> all <res/lock/proc> contexts -a <res> [<type>] all <res> pointers by an optional type -a convlock all converting enqueue (pointers) -A convlock all converting enqueue contexts -a convres all res ptr with converting enqueues -A convres all res contexts with converting enqueues

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ORADEBUG Continued...

-a name list all resource names -a hashcount list all resource hash bucket counts -t Traffic controller info -s summary of all enqueue types -k GES SGA summary info -m pkey <objectno> request for remastering this object at current instance -m dpkey <objectno> request for dissolving remastering of this object at current instance

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MemoryStructures

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Memory Areas An Oracle process includes

the following memory areas

Executable SGA Shared Libraries PGA/Session Heap Stack

40000000

20000000

Executable

PGASession Heap

SharedLibraries

SGA

Stack

STOPFFFFFFFF

00000000

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Shared Memory Shared memory areas can be dumped to trace file using

ORADEBUG SETMYPIDORADEBUG IPC

$ sqlplus /nologSQL> CONNECT SYS/<password> AS SYSDBAConnectedSQL> ORADEBUG SETMYPIDStatement processedSQL> ORADEBUG IPCInformation written to trace file

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Area #0 `Fixed Size' containing Subareas 0-0 Total size 0000000000129968 Minimum Subarea size 00000000 Area Subarea Shmid Stable Addr Actual Addr 0 0 65537 0x00000020000000 0x00000020000000 Subarea size Segment size 000000000012a000 0000000010800000 Area #1 `Variable Size' containing Subareas 2-2 Total size 0000000010000000 Minimum Subarea size 00400000 Area Subarea Shmid Stable Addr Actual Addr 1 2 65537 0x00000020400000 0x00000020400000 Subarea size Segment size 0000000010000000 0000000010800000 Area #2 `Redo Buffers' containing Subareas 1-1 Total size 00000000002d6000 Minimum Subarea size 00000000 Area Subarea Shmid Stable Addr Actual Add 2 1 65537 0x0000002012a000 0x0000002012a000 Subarea size Segment size 00000000002d6000 0000000010800000 Area #3 `skgm overhead' containing Subareas 3-3 Total size 0000000000001000 Minimum Subarea size 00000000 Area Subarea Shmid Stable Addr Actual Addr 3 3 65537 0x00000030400000 0x00000030400000 Subarea size Segment size 0000000000001000 0000000010800000

ORADEBUG IPC - Example

STOP

Area #0 `Fixed Size' containing Subareas 0-0 Total size 0000000000129968 Minimum Subarea size 00000000 Area Subarea Shmid Stable Addr Actual Addr 0 0 65537 0x00000020000000 0x00000020000000 Subarea size Segment size 000000000012a000 0000000010800000 Area #1 `Variable Size' containing Subareas 2-2 Total size 0000000010000000 Minimum Subarea size 00400000 Area Subarea Shmid Stable Addr Actual Addr 1 2 65537 0x00000020400000 0x00000020400000 Subarea size Segment size 0000000010000000 0000000010800000 Area #2 `Redo Buffers' containing Subareas 1-1 Total size 00000000002d6000 Minimum Subarea size 00000000 Area Subarea Shmid Stable Addr Actual Add 2 1 65537 0x0000002012a000 0x0000002012a000 Subarea size Segment size 00000000002d6000 0000000010800000 Area #3 `skgm overhead' containing Subareas 3-3 Total size 0000000000001000 Minimum Subarea size 00000000 Area Subarea Shmid Stable Addr Actual Addr 3 3 65537 0x00000030400000 0x00000030400000 Subarea size Segment size 0000000000001000 0000000010800000

Fixed Area

Variable Area

Redo Buffers

OS Specific

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Shared Global Area Contains

Fixed SGA Buffer Pool Shared Pool Oracle 7.0 and above Large Pool Oracle 8.0 and above Java Pool Oracle 8.1.5 and above Streams Pool Oracle 10.1 and above Redo buffers

Buffer Pool includes Default cache Keep and Recycle cache Oracle 8.0 and above 2K, 4K, 8K, 16K and 32K cache Oracle 9.0.1 and above

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V$SGAINFO Summarizes SGA pools

NAME VARCHAR2(32)BYTES NUMBERRESIZEABLE VARCHAR2(3)

SELECT * FROM v$sgainfo;

NAME BYTES RESIZEABLE-------------------------------- ---------- ----------Fixed SGA Size 1218920 NoRedo Buffers 2973696 NoBuffer Cache Size 176160768 YesShared Pool Size 83886080 YesLarge Pool Size 4194304 YesJava Pool Size 4194304 YesStreams Pool Size 0 YesGranule Size 4194304 NoMaximum SGA Size 272629760 NoStartup overhead in Shared Pool 46137344 NoFree SGA Memory Available 0

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Granules Introduced in Oracle 9.0.1

SGA divided into granules

In Oracle 9.2 Unix granule size dependent on SGA_MAX_SIZE 4 mb SGA_MAX_SIZE <= 128 mb 16 mb SGA_MAX_SIZE > 128 mb

If SGA_MAX_SIZE not set explicitly then defaults to sum of individual pool parameters

SGA_MAX_SIZE cannot be dynamically modified

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Granules In Oracle 10.1 and above

SGA_MAX_SIZE dependent on SGA_TARGET

Granule size dependent on SGA_MAX_SIZE 4 mb SGA_MAX_SIZE <= 256 mb?? 16 mb SGA_MAX_SIZE > 256 mb ??

Granule size can be controlled using _ksmg_granule_size unsupported parameter

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X$KSMGEIntroduced in Oracle 9.2Describes individual granules

ADDR RAW(4)INDX NUMBERINST_ID NUMBERGRANNUM NUMBERGRANTYPE NUMBERGRANSTATE VARCHAR2(16)GRANFLAGS NUMBERLOCALITY NUMBERKSMAREANUM NUMBERBASEADDR RAW(4)GRANSIZE NUMBERGRANNEXT NUMBERGRANPREV NUMBER

INVALID (Free)ALLOCATED

Granule Address

Granule Size

Next granule ID

Previous granule ID

Granule ID

0 Free1 Shared Pool2 Large Pool3 Java Pool6 Buffer Pool

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Granules

SGA_TARGET = 260M SGA_MAX_SIZE = 260M

GRANULE SIZE = 4M

256M

4M

Buffer Pool 172M

Fixed SGA + Redo Buffers 4M

Large Pool 4M

Shared Pool 76M

Java Pool 4M

STOP

This is an example of an SGA mapped using X$KSMGE

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V$SGASTAT Enhanced in Oracle 10.1 and above

Shared Pool 682Large Pool 6Java Pool 4Streams Pool 4

In Oracle 10.2 describes around 700 memory areas

POOL VARCHAR2(12)NAME VARCHAR2(26)BYTES NUMBER

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V$SGASTAT RAC-specific areas includegcs affinitygcs close objgcs commit sga stategcs I/O statistics structgcs mastership bucketsgcs opaque ingcs res hash bucketgcs res latch tablegcs resource freelist arrgcs resource freelist dyngcs resourcesgcs scan queue arraygcs shadow locks dyn seggcs shadow locks freelistgcs shadows

ges big msg buffersges deadlock xid freelistges deadlock xid hash tabges enqueue cur. usage peges enqueue max. usage peges enqueue multiple freeges enqueuesges ipc instance mapsges lmd process descriptoges lms process descriptoges process arrayges process hash tableges recovery domain tableges regular msg buffersges reserved msg buffers

ges res mastership bucketges resourceges resource hash seq tabges resource hash tableges resource poolsges scan queue arrayges shared global areaKCL buffer headerKCL instance cache transfKCL lock contextsKCL lock stateKCL name tableKCL partition tableKCL region arrayKJXM msg statistics table

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V$SGASTAT Significant RAC areas in Oracle 10.2

Name Size(bytes) Locationgcs resources 2298008 Segmented Arraygcs shadows 1632280 Segmented Arrayges resource 1257188 Heapges enqueues 1625344 Segmented Arrayges big msg buffers 3979396 Unknown

In Oracle 9.2 all five structures were stored in segmented arrays

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Permanent Areas

SELECT ksmchptr, ksmchsizFROM x$ksmspWHERE ksmchcls = 'perm';

Address Size

2D034000 3981312

2D434000 3549424

2D834000 39632362DC34000 39805842DFFFD28 7282E034000 3919532

Allocated at instance startup Contain structures such as

processes sessions segmented arrays

STOP

2AC000002B8000002BC000002C0000002C4000002C8000002CC000002D000000

2D8000002DC000002E0000002E4000002E8000002EF000002F0000002F4000002F8000002FC0000030000000

2D400000

PermanentArea

Heap

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X$KSMSP Externalises chunks in the shared pool

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKSMCHIDX NUMBERKSMCHDUR NUMBERKSMCHCOM VARCHAR2(16)KSMCHPTR RAW(4)KSMCHSIZ NUMBERKSMCHCLS VARCHAR2(8)KSMCHTYP NUMBERKSMCHPAR RAW(4)

Description of chunk type

Address of chunk

Size including header

Class●Perm●Recreate●Freeable●Free●R-Free●R-Freeable

Address of parent

Type (recreate only)●0x18 - KGL Handle●0x24 - Fixed Allocation●0x74 - KQR PO●0x80 - KQR SO●0xFFF - Extended header

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X$KSMSP Some RAC components are stored in the shared pool heap

SELECT ksmchcom, SUM(ksmchsiz), COUNT(*)FROM x$ksmspGROUP BY ksmchcom;

gcs_mastership 4620 1gcs_res_hash_bu 16396 1gcs_res_latch_t 7692 1ges_res_masters 3084 1ges_resource 619276 164

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Segmented Arrays Used to store arrays of objects

Array too large to fit in granule Array may grow dynamically

Objects using segmented arrays include enqueues (locks) enqueue resources (resources) transactions transaction branches

Segmented arrays managed recursively by segmented array

Segmented arrays externalised in X$KSMDD

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Segmented Arrays

SegmentedArrays

Call

Enqueues

EnqueueResources

SegmentedArray

HeaderSegmented

Array

SegmentedArray

Header

SegmentedArray

STOP

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X$KSMDD Externalises segmented array headers

ADDR RAW(4)INDX NUMBERINST_ID NUMBERNAME VARCHAR2(30)ELEMENTS_CHUNK NUMBERITEMS_PT NUMBERINITENTRIES NUMBERNUMENTRIES NUMBERCURENTRIES NUMBERNUMCHUNKS NUMBERELEMSIZE NUMBERFLAGS NUMBERHEAP RAW(4)SECONDARY RAW(4)

Name of array

Address of parent heap

Number of chunks

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Segmented Arrays In Oracle 10.2 there are three RAC-specific segmented arrays:

GCS Resources GCS Shadows GES Enqueues

In previous releases there were five segmented arrays: GCS Resources GCS Shadows GES Resources GES Shadows GES Messages

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Heaps A heap consists of one or more extents Each heap extent occupies a single granule Each extent contains one or more chunks Each heap has a header containing

list of used chunks list of free chunks

Extent 0 Extent 1 Extent 2HeapHeader

Free List Chunks

STOP

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X$KSMHP Externalises chunks in the heap

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKSMCHDS RAW(4)KSMCHCOM VARCHAR2(16)KSMCHPTR RAW(4)KSMCHSIZ NUMBERKSMCHCLS VARCHAR2(8)KSMCHTYP NUMBERKSMCHPAR RAW(4)KSMCHOWN RAW(4)

Can only be accessed using KSMCHDS e.g.SELECT * FROM x$ksmhpWHERE ksmchds = HEXTORAW ('2CA54040');

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The BufferCache

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Buffer Headers Each buffer has a buffer header Buffer headers are stored in same granule as buffers Buffer headers include

Replacement list Hash list Pointer to buffer In RAC only pointer to Lock Element Buffer

Headers

Granule

Buffers

STOP

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X$BHADDR RAW(4)INDX NUMBERINST_ID NUMBERHLADDR RAW(4)BLSIZ NUMBERNXT_HASH RAW(4)PRV_HASH RAW(4)NXT_REPL RAW(4)PRV_REPL RAW(4)FLAG NUMBERRFLAG NUMBERSFLAG NUMBERLRU_FLAG NUMBERTS# NUMBERFILE# NUMBERDBARFIL NUMBERDBABLK NUMBER

CLASS NUMBERSTATE NUMBERMODE_HELD NUMBERCHANGES NUMBERCSTATE NUMBERLE_ADDR RAW(4)DIRTY_QUEUE NUMBERSET_DS RAW(4)OBJ NUMBERBA RAW(4)CR_SCN_BAS NUMBERCR_SCN_WRP NUMBERCR_XID_USN NUMBERCR_XID_SLT NUMBERCR_XID_SQN NUMBERCR_UBA_FIL NUMBERCR_UBA_BLK NUMBER

CR_UBA_SEQ NUMBERCR_UBA_REC NUMBERCR_SFL NUMBERCR_CLS_BAS NUMBERCR_CLS_WRP NUMBERLRBA_SEQ NUMBERLRBA_BNO NUMBERHSCN_BAS NUMBERHSCN_WRP NUMBERHSUB_SCN NUMBERUS_NXT RAW(4)US_PRV RAW(4)WA_NXT RAW(4)WA_PRV RAW(4)TCH NUMBERTIM NUMBER

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Head of Cold End

Head of Hot End

Single-Block Reads

92

0

34

3

72

4

52

1

71

2

66

0

49

0

42

1

45

2

52

1

71

2

66

0

42

1

11

1

52

1

71

2

11

1

42

1

42

2

71

0

92

0

34

3

72

4

45

2

11

1

52

1

42

2

33

1

45

2

11

1

42

2

33

1

34

4

92

0

34

4

72

4

45

2

11

1

42

0

33

1

71

0

87

1

87

1

72

4

33

1

45

2

Read Block 42

Get first available buffer from cold endUpdate buffer contentsInsert buffer at head of cold end

Read Block 11

Get first available buffer from cold endUpdate buffer contentsInsert buffer at head of cold end

Read Block 42

Update touch count for block 42

Read Block 33

Move block 71 to head of hot endSet touch count on block 71 to zeroGet first available bufferfrom cold endUpdate buffer contentsInsert buffer at head of coldend

Read Block 34

Update touch countfor block 34

Read Block 87

Move block 42 to headof hot endSet touch counton block 42 to zeroGet first available bufferfrom cold endUpdate buffer contentsInsert buffer at head of coldend

STOP

Block Number

Touch Count

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Multi-Block Reads

Head of Cold End

Head of Hot End

Read Block 1

Get first four available buffers from cold endRead next four blocks into buffers

1 2 3 4

Insert buffers at head of cold end

12 13 2 14 3 2 1

Move block 1 to cold end

121

Read Block 2


21 321 3 4

Read Block 3


Read Block 4


Read Block 5

Get next four available buffers from cold endRead next four blocks into buffersInsert buffers at head of cold endMove block 5 to cold end

4 3 2 15

5 56

76

7 6 5

8

78 5 56 5 65 6 75 6 7 8

Read Block 6


Read Block 7


Read Block 8


STOP

DB_FILE_MULTIBLOCK_READ_COUNT = 4

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GlobalCache

Services

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Read with No Transfer

Instance 1

Instance 2

Instance 4

1318

Request shared resource

Instance 3

ResourceMaster

Instance 2 requests current read on block

Request granted

SN

Read request

Block returned

1318

1

2

3

4

STOP

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Read to Write Transfer

Instance 1

Instance 2

Instance 4

1318

Request exclusiveresource

Instance 3

ResourceMaster

Instance 1 requests exclusive read on block

Transfer block to Instance 1 for

exclusiveaccess

SNBlock and resource status

Resource status

1318

1

2

3

4

N

N

X

1320

STOP

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Write to Write Transfer

Instance 1

Instance 2

Instance 4

1318

Request block in exclusive mode

Instance 3

ResourceMaster

Instance 4 requests exclusive read on block

Transfer block to Instance 4 in exclusive

mode

SN

Block and resource status

Resource status

1318

12

3

4N NX

1320N

N

X1320 1323

STOP

Note that Instance 1 will create a past image (PI) of the dirty block

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Past Images When an instance passes a dirty block to another instance it

Flushes redo buffer to redo log

Retains past image (PI) of block in buffer cache PI is retained until another instance writes block to disk Used to reduce recovery times

Recorded in V$BH.STATUS as PI Based on X$BH.STATE (value 8 in Oracle 10.2)

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Past Images

13281329UPDATE t1SET c1 = 1324;COMMIT;

UPDATE t1SET c1 = 1329;COMMIT;

1323

Instance 1

13231324132513261327

Buffer Cache

13241323

13251324

13261325

13271326

1328

13281327

Redo Log 1

Instance 2

Buffer Cache

13291328




UPDATE t1SET c1 = 1328;COMMIT; 1328

1323

Redo Log 2

1323

132813291329

1329

1329

Assume table t1 contains a single row in block 42

Instance 1 updates column to 1324Block 42 is read from diskUndo/Redo written to

Redo Log 1Block 42 is updated in buffer

cacheInstance 1 updates column to

1325Undo/Redo written to












1329GCS transfers block from Instance 1 to Instance 2

Instance 1 makes block 42 a Past Image blockUndo/redo written to


cacheInstance 2 Crashes

Contents of buffer cache are lostDBWR has not written changes

to block 42 back to disk yetInstance 1 must perform recovery for Instance 2

Block 42 needs recoveryInstance 1 uses Past Image Undo/redo is applied from

Redo Log 2Block 42 is subsequently written

back to disk by DBWR

STOP

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Write to Read Transfer

Instance 1

Instance 2

Instance 4

1318

Request block in shared mode

Instance 3

ResourceMaster

Instance 2 requests current read on block

SN

Block and resource status

Resource status

1318

1

3

4

N NX1320

N

N

X1320 1323

Transferblock to Instance 1in sharedmode

2

S

S

STOP

Note that in recent versions _fairness_threshold is used to avoid unnecessary lock conversions

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Fairness Threshold Intended to prevent unnecessary lock downgrades when other

instances only require read-only copies

For write to read transfers Writing instance retains X lock Reading instance retains null lock

If _fairness_threshold reached then Writing instance downgrades X lock to S lock Reading instance receives S lock

_fairness_threshold default value is 4

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Fairness Threshold

Assume instance 1 holds exclusive lock on block

Instance 2

Instance 2 requests consistent readInstance 1 sets counter to 1Instance 1 sends block to

Instance 2

13231323

Instance 1

X

Instance 2 receives block with Null lock

13231323

01234 N


Instance 2Instance 2 receives block with

Null lock

1323


instance 2Instance 2 receives block with

Null lockInstance 2 requests consistent

readInstance 1 sets counter to 4Instance 1 downgrades lock from X to S

S

Instance 1 sends block to Instance 2

Instance 2 receives block with Shared lock

S

_fairness_threshold = 4

STOP

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Lock Elements Contain embedded GCS Client structures (KJBL)

LockElement

GCSClient

BufferHeader

LockElement

GCSClient

BufferHeader

BufferHeader

LockElement

GCSClient

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V$LOCK_ELEMENT Based on X$LE

LOCK_ELEMENT_ADDR RAW(4)INDX NUMBERCLASS NUMBERLOCK_ELEMENT_NAME NUMBERMODE_HELD NUMBERBLOCK_COUNT NUMBERRELEASING NUMBERACQUIRING NUMBERINVALID NUMBERFLAGS NUMBER

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X$LEADDR RAW(4)INDX NUMBERINST_ID NUMBERLE_ADDR RAW(4)NAME NUMBERLE_CLASS NUMBERLE_RLS NUMBERLE_ACQ NUMBERLE_FLAGS NUMBERLE_MODE NUMBERLE_WRITE NUMBERLE_LOCAL NUMBERLE_RECOVERY NUMBERLE_BLKS NUMBERLE_TIME NUMBERLE_KJBL RAW(4)

BufferHeader

LockElement

GCSClient

STOP

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Global Cache Services

KJBRKJBR

KJBL

BH BH

LE

KJBL

LE

KJBL

GCSClient

GCSShadow

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GCS Parameters GCS Resources

Number of GCS resource structures determined by _gcs_resources parameter

Stored in segmented array Externalized in X$KJBR Number of free GCS resource structures in X$KJBRFX

GCS Enqueues (Shadows/Clients) Number of GCS enqueue structures determined by

_gcs_shadow_locks parameter Stored in segmented array Externalized in X$KJBL Number of free GCS enqueue structures in X$KJBLFX

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X$KJBR Externalizes GCS Resources

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKJBRRESP RAW(4)KJBRGRANT VARCHAR2(9)KJBRNCVL VARCHAR2(9)KJBRROLE NUMBERKJBRNAME VARCHAR2(30)KJBRMASTER NUMBERKJBRGRANTQ RAW(4)KJBRCVTQ RAW(4)KJBRWRITER RAW(4)

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X$KJBL Externalizes GCS Enqueues

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKJBLLOCKP RAW(4)KJBLGRANT VARCHAR2(9)KJBLREQUEST VARCHAR2(9)KJBLROLE NUMBERKJBLRESP RAW(4)KJBLNAME VARCHAR2(30)KJBLNAME2 VARCHAR2(30)KJBLQUEUE NUMBERKJBLLOCKST VARCHAR2(64)KJBLWRITING NUMBERKJBLREQWRITE NUMBERKJBLMASTER NUMBERKJBLBLOCKED NUMBERKJBLBLOCKER NUMBER

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Global Cache Dumps To dump the contents of the global cache use:

ALTER SESSION SET EVENTS 'IMMEDIATE TRACE NAME GC_ELEMENTS LEVEL 1';

GLOBAL CACHE ELEMENT DUMP (address: 0x21fecd18): id1: 0x3591 id2: 0x10000 obj: 181 block: (1/13713) lock: SL rls: 0x0000 acq: 0x0000 latch: 0 flags: 0x41 fair: 0 recovery: 0 fpin: 'kdswh05: kdsgrp' bscn: 0x0.18a9c bctx: (nil) write: 0 scan: 0x0 xflg: 0 xid: 0x0.0.0

GCS CLIENT 0x21fecd60,1 sq[(nil),(nil)] resp[(nil),0x3591.10000] pkey 181grant 1 cvt 0 mdrole 0x21 st 0x20 GRANTQ rl LOCALmaster 1 owner 0 sid 0 remote[(nil),0] hist 0x7chistory 0x3c.0x1.0x0.0x0.0x0.0x0. cflag 0x0 sender 2 flags 0x0 replay# 0disk: 0x0000.00000000 write request: 0x0000.00000000pi scn: 0x0000.00000000msgseq 0x1 updseq 0x0 reqids[1,0,0] infop 0x0pkey 181hv 107 [stat 0x0, 1->1, wm 32767, RMno 0, reminc 6, dom 0]kjga st 0x4, step 0.0.0, cinc 8, rmno 10, flags 0x0lb 0, hb 0, myb 178, drmb 178, apifrz 0

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Global Cache Dumps Continued

GLOBAL CACHE ELEMENT DUMP (address: 0x237f4358): id1: 0x6a39 id2: 0x10000 obj: 74 block: (1/27193) lock: SL rls: 0x0000 acq: 0x0000 latch: 0 flags: 0x41 fair: 0 recovery: 0 fpin: 'kdswh05: kdsgrp' bscn: 0x0.26992 bctx: (nil) write: 0 scan: 0x0 xflg: 0 xid: 0x0.0.0

GCS SHADOW 0x237f43a0,1 sq[0x2ee64e8c,0x2eff3858] resp[0x2ee64e74,0x6a39.10000] pkey 74 grant 1 cvt 0 mdrole 0x21 st 0x40 GRANTQ rl LOCAL master 0 owner 0 sid 0 remote[(nil),0] hist 0x12a5 .....

GCS RESOURCE 0x2ee64e74 hashq [0x2ee61894,0x2ff57390] name[0x6a39.10000] pkey 74 grant 0x2eff3858 cvt (nil) send (nil),0 write (nil),0@65535

flag 0x0 mdrole 0x1 mode 1 scan 0 role LOCAL ..... GCS SHADOW 0x2eff3858,1 sq[0x237f43a0,0x2ee64e8c] resp[0x2ee64e74,0x6a39.10000] pkey 74 grant 1 cvt 0 mdrole 0x21 st 0x40 GRANTQ rl LOCAL

master 0 owner 1 sid 0 remote[0x23fea160,1] hist 0x65f .....

GCS SHADOW 0x237f43a0,1 sq[0x2ee64e8c,0x2eff3858] resp[0x2ee64e74,0x6a39.10000] pkey 74 grant 1 cvt 0 mdrole 0x21 st 0x40 GRANTQ rl LOCAL master 0 owner 0 sid 0 remote[(nil),0] hist 0x12a5 .....

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Block Mastering Each block is mastered on one instance

Block DBA is reported by X$KJBR.KJBRNAME

Names for have the format: [<block_number>][<file_number>],[BL]

Ordering by X$KJBR.KJBRNAME is difficult because the resource names do not collate e.g.

[0x900][0x70000],[BL] [0x90][0x70000],[BL]

Current master reported by X$KJBR.KJBRMASTER

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Block Mastering In Oracle 10.2 block mastering is determined by

_lm_contiguous_res_count Specifies number of contiguous blocks that will hash to the

same HV bucket Defaults to 128 For example

Start End

0x080 0x0FF

0x180 0x1FF0x280 0x2FF0x380 0x3FF0x480 0x4FF0x580 0x5FF

etc etc

Start End

0x000 0x07F

0x100 0x17F0x200 0x27F0x300 0x37F0x400 0x47F0x500 0x57F

etc etc

Instance 0 Instance 1

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Block Mastering In Oracle 9.2 (and probably 10.1) block mastering determined

by hash function Algorithm applied to groups of 1289 contiguous blocks

In two node cluster instance 0 has 645 blocks instance 1 has 644 blocks

In three node cluster instance 0 has 430 blocks instance 2 has 215 blocks instance 1 has 430 blocks instance 2 has 214 blocks

Beware of small hot tables and indexes....

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Dynamic Remastering In Oracle 9.2

documentation describes dynamic remastering not implemented in code

In Oracle 10.1 work at data file level very high threshold so difficult to test does occur on some customer sites may cause LMON process to crash in 10.1.0.4

bug 3659289 - patch available fixed in 10.1.0.5/10.2.0.1

In Oracle 10.2 works at object level thresholds are relatively low

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Dynamic Remastering Example

SELECT data_object_id FROM dba_objectsWHERE owner = 'US01'AND object_name = 'T1';

OBJECT_ID---------52084

ORADEBUG LKDEBUG -m pkey 52084

To remaster object at current instance use:

All blocks now mastered by the current instance

To redistribute masters to all available instances use:

ORADEBUG LKDEBUG -m dpkey 52084

Blocks mastered by both (all) instances again

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V$GCSPFMASTER_INFO Object re mastering is recorded in V$GCSPFMASTER_INFO

FILE_ID NUMBEROBJECT_ID NUMBERCURRENT_MASTER NUMBERPREVIOUS_MASTER NUMBERREMASTER_CNT NUMBER

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Dynamic Remastering Object remastering recorded in V$GCSPFMASTER_INFO Instances are internally numbered 0, 1 etc Initially contains no rows After remastering object 52084 to instance 0

SELECT object_id, current_master, previous_master FROM v$gcspfmaster_info;

After remastering object 52084 to instance 1

Object ID Current Master Previous Master52084 0 32767

Object ID Current Master Previous Master52084 1 0

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Dynamic Remastering Information about Dynamic Remastering operations is also

recorded in the following fixed views

X$KJDRMREQ Dynamic Remastering Requests

X$KJDRMAFNSTATS File Remastering Statistics

X$KJDRMHVSTATS Hash Value Statistics

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The LibraryCache

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Library Cache Object - Parent

16 x 1 wordpointers

KGLHD

ParentObject

KGLNA

SELECT SUM (c2) FROM t1WHERE c3 = 42 AND c4 < 2004

ParentName

ChildHandle

KGLHD

Child 1

Child 2

Heap 0

KGLOB

X$KGLOBParentHandle

KGLHD

STOP

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Library Cache Object - Child

KGLHD

ChildHandle

ChildObject

SELECTStatement

Heap 6

KGLOB

SubheapHeader

SubheapHeader

Heap 0

SubqueryHeader

Statistics,Optimizer

Environment,BindVariables

X$KGLOB

STOP

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Library Cache In general

Locks are required for parsing Externalized in X$KGLLK

Pins are required for execution Externalized in X$KGLPN

Each KGLHD structure has a set of double linked lists including; Locks Pins

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X$KGLPN

X$KGLLK

Library Cache Object - Locks & Pins

ChildHandle

ChildObject

KGLOB

X$KGLOB

STOP

LockLock

Pin

Lock

Pin Pin

KGLHD

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Namespaces In Oracle 10.2 there are 64 library cache namespaces Externalized by KGLHDNSP in X$KGLOB

CRSR LOB REIP RMGR JVSD RELS MVOBINX NSCPDTABL DIR CPOB XDBS STFG RELD STBO JSLVBODY QUEU EVNT PPLN TRANS IFSD HTSO MODLTRGR OBJG SUMM PCLS RELC XDBC JSGA UnusedINDX PROP DIMM SUBS RULE USAG JSET UnusedCLST JVSC CTS LOCS STRM MVOBTBL TABLE UnusedKGLT JVRE OUTL RMOB REVC JSQI CLST UnusedPIPE ROBJ RULS RSMD STAP CDC INDX Unused

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Namespaces Library cache statistics can be dumped using:

ALTER SESSION SET EVENTS'IMMEDIATE TRACE NAME LIBRARY_CACHE LEVEL 1';

For example:

LIBRARY CACHE STATISTICS:namespace gets hit ratio pins hit ratio reloads invalids-------------- --------- --------- --------- --------- ---------- ----------CRSR 2403 0.086 33698 0.933 435 0TABL 4368 0.578 10032 0.657 961 0BODY 127 0.717 211 0.801 4 0TRGR 4 0.000 45 0.911 0 0INDX 81 0.272 83 0.036 21 0CLST 101 0.921 264 0.958 3 0KGLT 0 0.000 0 0.000 0 0PIPE 0 0.000 0 0.000 0 0LOB 0 0.000 0 0.000 0 0DIR 0 0.000 0 0.000 0 0QUEU 156 0.904 5886 0.997 0 0....

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V$LIBRARYCACHE Subset of rows from X$KGLST Contains 11 rows in Oracle 10.2

NAMESPACE VARCHAR2(15)GETS NUMBERGETHITS NUMBERGETHITRATIO NUMBERPINS NUMBERPINHITS NUMBERPINHITRATIO NUMBERRELOADS NUMBERINVALIDATIONS NUMBERDLM_LOCK_REQUESTS NUMBERDLM_PIN_REQUESTS NUMBERDLM_PIN_RELEASES NUMBERDLM_INVALIDATION_REQUESTS NUMBERDLM_INVALIDATIONS NUMBER

RAC Specific

Statistics

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SELECT inst_id, DECODE (indx,

0,'SQL AREA',1,'TABLE/PROCEDURE',2,'BODY',3,'TRIGGER', 4,'INDEX',5,'CLUSTER',6,'OBJECT',7,'PIPE',13,'JAVA SOURCE',14,'JAVA RESOURCE',32,'JAVA DATA','

?'), kglstget,kglstght, DECODE (kglstget,0,1,kglstght/kglstget),kglstpin,kglstpht, DECODE (kglstpin,0,1,kglstpht/kglstpin),kglstrld,kglstinv, kglstlrq,kglstprq,kglstprl,kglstirq,kglstmiv FROM x$kglst WHERE indx<8 OR indx=13 OR indx=14 OR indx=32

V$LIBRARYCACHE Based on X$KGLST

Names are generated in dynamic performance view

Only selected rows from X$KGLST

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X$KGLST Contains one row for each namespace (59 rows in 10.2)

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKGLSTCMS NUMBERKGLSTCHT NUMBERKGLSTGET NUMBERKGLSTGHT NUMBERKGLSTPIN NUMBERKGLSTPHT NUMBERKGLSTRLD NUMBERKGLSTINV NUMBERKGLSTLRQ NUMBERKGLSTPRQ NUMBERKGLSTPRL NUMBERKGLSTIRQ NUMBERKGLSTMIV NUMBER

RAC Specific

Statistics

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V$LOCK_TYPE Introduced in Oracle 10.1 Lists all lock types Wildcards for

Library Cache Locks and Pins Row Cache Locks

TYPE VARCHAR2(64)NAME VARCHAR2(64)ID1_TAG VARCHAR2(64)ID2_TAG VARCHAR2(64)IS_USER VARCHAR2(3)DESCRIPTION VARCHAR2(4000)

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Library Cache Objects Library Cache Objects can be dumped using:

ALTER SESSION SET EVENTS'IMMEDIATE TRACE NAME LIBRARY_CACHE LEVEL 4';

BUCKET 127469:LIBRARY OBJECT HANDLE: handle=2bb8dfbc mutex=0x2bb8e070(0)name=US01.T1hash=b2f454b86387761e02fc7e686e37f1ed timestamp=01-14-2006 22:04:06namespace=TABL flags=KGHP/TIM/MED/[40000000]kkkk-dddd-llll=0000-0701-0701 lock=0 pin=0 latch#=1 hpc=0002 hlc=0002lwt=0x2bb8e018[0x2bb8e018,0x2bb8e018] ltm=0x2bb8e020[0x2bb8e020,0x2bb8e020]pwt=0x2bb8dffc[0x2bb8dffc,0x2bb8dffc] ptm=0x2bb8e004[0x2bb8e004,0x2bb8e004]ref=0x2bb8e038[0x2bb8e038,0x2bb8e038] lnd=0x2bb8e044[0x2bb7a7ac,0x2bb8e410]

LOCK INSTANCE LOCK: id=LBb2f454b86387761ePIN INSTANCE LOCK: id=NBb2f454b86387761e mode=S release=F flags=[00INVALIDATION INSTANCE LOCK: id=IV0000c9890e170507 mode=SLIBRARY OBJECT: object=2caede30type=TABL flags=EXS/LOC[0005] pflags=[0000] status=VALD load=0

BUCKET 127469 total object count=1

For example:

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Library Cache Instance Locks Instance Locks created for

Library Cache Locks Library Cache Pins

Lock name based on object hash value (KGLNAHSH) For example:

BUCKET 127469:LIBRARY OBJECT HANDLE: handle=2bb8dfbc mutex=0x2bb8e070(0)name=US01.T1hash=b2f454b86387761e02fc7e686e37f1ed timestamp=01-14-2006 22:04:06namespace=TABL flags=KGHP/TIM/MED/[40000000]kkkk-dddd-llll=0000-0701-0701 lock=0 pin=0 latch#=1 hpc=0002 hlc=0002lwt=0x2bb8e018[0x2bb8e018,0x2bb8e018] ltm=0x2bb8e020[0x2bb8e020,0x2bb8e020]pwt=0x2bb8dffc[0x2bb8dffc,0x2bb8dffc] ptm=0x2bb8e004[0x2bb8e004,0x2bb8e004]ref=0x2bb8e038[0x2bb8e038,0x2bb8e038] lnd=0x2bb8e044[0x2bb7a7ac,0x2bb8e410]

LOCK INSTANCE LOCK: id=LBb2f454b86387761ePIN INSTANCE LOCK: id=NBb2f454b86387761e mode=S release=F flags=[00INVALIDATION INSTANCE LOCK: id=IV0000c9890e170507 mode=SLIBRARY OBJECT: object=2caede30type=TABL flags=EXS/LOC[0005] pflags=[0000] status=VALD load=0

BUCKET 127469 total object count=1

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Library Cache Instance Locks For example in library cache dump

Library cache pin instance lock is id=NBb2f454b86387761e

In X$KJIRFT this KJIRFTRN column [0xb2f454b8][0x6387761e],[NB]

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Namespaces->Instance Locks Slide 1 of 3

Namespace Lock PinJVSC LN NNJVRE LO NOROBJ LP NPREIP LQ NQCPOB LR NREVNT LS NSSUMM LT NTDIMM LU NUCTS LV NV

OUTL LW NWRULS LX NXRMGR LY NYXDBS LZ NZ

Namespace Lock PinCRSR LA NATABL LB NBBODY LC NCTRGR LD NDINDX LE NECLST LF NFKGLT LG NGPIPE LH NHLOB LI NIDIR LJ NJ

QUEU LK NKOBJG LL NLPROP LM NM

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Namespace Lock PinSTAP EN GNRELS EO GORELD EP GPIFSD EQ GQXDBC ER GRUSAG ES GS

MVOBTBL ET GTJSQI EU GUCDC EV GV

MVOBINX EW GWSTBO EX GXHTSO EY GYJSGA EZ GZ

Namespace Lock PinPPLN EA GAPCLS EB GBSUBS EC GCLOCS ED GDRMOB EE GERSMD EF GFJVSD EG GGSTFG EH GH

TRANS EI GIRELC EJ GJRULE EK GKSTRM EL GLREVC EM GM

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Namespace Lock PinJSET VA YA

TABLE VB YBCLST VC YCINDX VD YD

NSCPD VE YEJSLV VF YFMODL VG YG

Unused VH YHUnused VI YIUnused VJ YJUnused VK YKUnused VL YLUnused VM YM

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V$ROWCACHECACHE# NUMBERTYPE VARCHAR2(11)SUBORDINATE# NUMBERPARAMETER VARCHAR2(32)COUNT NUMBERUSAGE NUMBERFIXED NUMBERGETS NUMBERGETMISSES NUMBERSCANS NUMBERSCANMISSES NUMBERSCANCOMPLETES NUMBERMODIFICATIONS NUMBERFLUSHES NUMBERDLM_REQUESTS NUMBERDLM_CONFLICTS NUMBERDLM_RELEASES NUMBER

RAC Specific

Statistics

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V$ROWCACHE Based on X$KQRST Contains 42 rows in Oracle 10.2

34 Parent Cache 8 Subordinate Caches

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Row Caches->Instance Locks Slide 1 of 2

Cache# Namespace Lock0 dc_tablespaces QA1 dc_free_extents QB2 dc_segments QC3 dc_rollback_segments QD4 dc_used_extents QE5 dc_tablespace_quotas QF6 dc_files QG7 dc_users QH8 dc_objects QI9 dc_qmc_cache_entries QJ

10 dc_usernames QK11 dc_object_ids QL12 dc_constraints QM

Cache# Namespace Lock13 dc_sequences QN14 dc_profiles QO15 dc_database_links QP16 dc_histogram_defs QQ17 dc_global_oids QR18 dc_outlines QS19 dc_table_scns QT20 rule_info QU21 rule_or_piece QV22 dc_awr_control QW23 dc_qmc_ldap_cache... QX24 outstanding_alerts QY25 dc_hintsets QZ

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Row Caches->Instance Locks Slide 2 of 2

Cache# Namespace Lock26 global_database_name ??27 qmtmrcin_cache_entries ??28 qmtmrctn_cache_entries ??29 qmtmrcip_cache_entries ??30 qmtmrctp_cache_entries ??31 qmtmrciq_cache_entries ??32 qmtmrctq_cache_entries ??33 kqlsubheap_object ??

Cache# = KQRSTCID

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Row Caches Row cache statistics can be dumped using:

ALTER SESSION SET EVENTS'IMMEDIATE TRACE NAME ROW_CACHE LEVEL 1';

For example:

ROW CACHE STATISTICS:cache size gets misses hit ratio DLM req-------------------------- ------- ------- ------ --------- -------dc_tablespaces 496 8909 7 0.999 7dc_free_extents 388 0 0 0.000 0dc_segments 444 4191 569 0.880 709dc_rollback_segments 452 4210 31 0.993 74dc_used_extents 400 0 0 0.000 0dc_tablespace_quotas 396 0 0 0.000 0dc_files 412 0 6 0.000 6dc_users 520 9042 23 0.997 23 dc_users 260 0 0 0.000 0 dc_user_grants 108 24 17 0.585 0 dc_app_role 100 0 0 0.000 0....

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BUCKET 48205: row cache parent object: address=0x2bb8dcd8 cid=8(dc_objects) hash=313bbc4c typ=9 transaction=(nil) flags=00000002 own=0x2bb8dd44[0x2bb8dd44,0x2bb8dd44] wat=0x2bb8dd4c[0x2bb8dd4c,0x2bb8dd4c] mode=S status=VALID/-/-/-/-/-/-/-/- request=N release=FALSE flags=0 instance lock id=QI f611ffad e31d1de3 set=0, complete=FALSE data= 00000037 31540002 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 ...... 00000000 00000000 00000000 0000c989 00000001 0000c989 016a7802 0705170e 0e016a78 78070517 170e016a 00010705 00000000 00000000 00000000 00000000 00000000 00000006 BUCKET 48205 total object count=1

Row Caches Row cache statistics can be dumped using:

ALTER SESSION SET EVENTS'IMMEDIATE TRACE NAME ROW_CACHE LEVEL 8';

For example:

T1

Instance LockQI F611FFAD E31D1DE3

Cache ID 8dc_objects

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GESResource

Global Enqueue Services

KJIRFT

KJILKFTGES

EnqueueKJILKFT KJILKFT

KJILKFTKJILKFT

KJILKFT

Holders Converters Waiters

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Resource Names Contain

1 x two byte name 2 x 32 bit integer tag fields

Used with Resources Enqueues Locks Global Enqueue Services

Global Cache Services Block are resources with resource name BL

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Resource Names Externalized inconsistently throughout Oracle in

V$/GV$ dynamic performance views X$ fixed tables Dumps and trace files

Stored consistently in internal C structures including KJBR KJIRFT

Other structures reference the resource names in these structures including KJBL KJILFKT

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GES Parameters GES Resources

Number of GES resource structures probably determined by

_lm_ress parameter Stored in heap Externalized in X$KJIRFT

GES Enqueues Number of GES enqueue structures probably determined

by _lm_locks parameter

Stored in segmented array Externalized in X$KJILKFT

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X$KJIRFT Externals global enqueue resources Does NOT include global cache resources

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKJIRFTRP RAW(4)KJIRFTRN VARCHAR2(30)KJIRFTCQ NUMBERKJIRFTGQ NUMBERKJIRFTPR NUMBERKJIRFTRDN VARCHAR2(25)KJIRFTMN NUMBERKJIRFTNCL VARCHAR2(9)KJIRFTVS VARCHAR2(32)KJIRFTVB VARCHAR2(64)

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X$KJILKFT

ADDR RAW(4)INDX NUMBERINST_ID NUMBERKJILKFTLKP RAW(4)KJILKFTGL VARCHAR2(9)KJILKFTRL VARCHAR2(9)KJILKFTRP RAW(4)KJILKFTRN1 VARCHAR2(30)KJILKFTRN2 VARCHAR2(30)KJILKFTPID NUMBERKJILKFTXID0 NUMBERKJILKFTXID1 NUMBERKJILKFTGID NUMBERKJILKFTOODD NUMBERKJILKFTOOPT NUMBERKJILKFTOOPO NUMBER

KJILKFTOONXID NUMBERKJILKFTCOGV NUMBERKJILKFTCOPV NUMBERKJILKFTCONV NUMBERKJILKFTCODV NUMBERKJILKFTCONQ NUMBERKJILKFTCOEP NUMBERKJILKFTCONDDW NUMBERKJILKFTCONDDB NUMBERKJILKFTWQ NUMBERKJILKFTLS VARCHAR2(64)KJILKFTASTE0 NUMBERKJILKFTON NUMBERKJILKFTBLKED NUMBERKJILKFTBLKER NUMBER

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V$GES_RESOURCE Contains rows from both KJIRFT and KJBR Synonym for V$DLM_RESS

RESP RAW(4)RESOURCE_NAME VARCHAR2(30)ON_CONVERT_Q NUMBERON_GRANT_Q NUMBERPERSISTENT_RES NUMBERMASTER_NODE NUMBERNEXT_CVT_LEVEL VARCHAR2(9)VALUE_BLK_STATE VARCHAR2(32)VALUE_BLK VARCHAR2(64)

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V$GES_RESOURCE Contains rows from both KJIRFT and KJBR Synonym for V$DLM_RESS

SELECT inst_id, kjirftrp, kjirftrn, kjirftcq, kjirftgq, kjirftpr, kjirftmn, kjirftncl, kjirftvs, kjirftvb

FROM x$kjirft UNION ALL SELECT

inst_id, kjbrresp, kjbrname, DECODE (kjbrcvtq, '00', 0, 1),DECODE (kjbrgrantq, '00', 0, 1), 1, kjbrmaster, kjbrncvl,'KJUSERVS_NOVALUE', '0x0'

FROM x$kjbr

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V$GES_ENQUEUE Contains rows from both KJILKFT and KJBL

HANDLE RAW(4)GRANT_LEVEL VARCHAR2(9)REQUEST_LEVEL VARCHAR2(9)RESOURCE_NAME1 VARCHAR2(30)RESOURCE_NAME2 VARCHAR2(30)PID NUMBERTRANSACTION_ID0 NUMBERTRANSACTION_ID1 NUMBERGROUP_ID NUMBEROPEN_OPT_DEADLOCK NUMBEROPEN_OPT_PERSISTENT NUMBEROPEN_OPT_PROCESS_OWNED NUMBEROPEN_OPT_NO_XID NUMBER

CONVERT_OPT_GETVALUE NUMBERCONVERT_OPT_PUTVALUE NUMBERCONVERT_OPT_NOVALUE NUMBERCONVERT_OPT_DUBVALUE NUMBERCONVERT_OPT_NOQUEUE NUMBERCONVERT_OPT_EXPRESS NUMBERCONVERT_OPT_NODEADLOCKWAIT NUMBERCONVERT_OPT_NODEADLOCKBLOCK NUMBERWHICH_QUEUE NUMBERSTATE VARCHAR2(64)AST_EVENT0 NUMBEROWNER_NODE NUMBERBLOCKED NUMBERBLOCKER NUMBER

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V$GES_ENQUEUE Contains rows from both KJILKFT and KJBL

SELECT inst_id, kjilkftlkp, kjilkftgl, kjilkftrl, kjilkftrn1, kjilkftrn2, kjilkftpid,kjilkftxid0, kjilkftxid1, kjilkftgid, kjilkftoodd, kjilkftoopt, kjilkftoopo,kjilkftoonxid, kjilkftcogv, kjilkftcopv, kjilkftconv, kjilkftcodv, kjilkftconq,kjilkftcoep, kjilkftconddw, kjilkftconddb, kjilkftwq, kjilkftls, kjilkftaste0,kjilkfton, kjilkftblked, kjilkftblker

FROM x$kjilkft UNION ALL SELECT inst_id,

kjbllockp, kjblgrant, kjblrequest, kjblname, kjblname2, 0, 0, 0, 0, 0, 1, 0, 1,0, 0, 0, 0, 0, 0, 0, 0, kjblqueue, kjbllockst, 0, kjblowner, kjblblocked,

kjblblocker FROM x$kjbl

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Thank you for your interest

For more information and to provide feedback

please contact me

My e-mail address is:[email protected]

My website address is:

www.juliandyke.com

Inside RAC

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