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오라클 LOCK TYPE 과 LOCK MODE

DB CAFE

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1 오라클 LOCK TYPE 과 LOCK MODE[편집]

  1. Oracle Lock 은 Lock Type 과 Lock Mode 가 있음

2 Lock Type[편집]

  • 락이 발생한 대상(Target)을 가르킴
  1. Lock 이 Temp Tablespace 에서 발생한 건지,
  2. Undo Segment 에서 발생한 건지,
  3. Log Miner 와 관계된 건지를 확인
  • 대표적인 Lock Type 은 'TX' (Transaction Lock), 'TM' (Table Lock) 등이 있고, 약 290여개 Lock Type 이 존재

3 Lock Mode[편집]

  • 락을 어떤식으로 걸었는지 와 강도(Intensity)를 의미
  1. share , row share
  2. exclusive, row exclusive 등등


4 Lock Type 종류[편집]

  • V$LOCK_TYPE
TYPE       NAME                                     DESCRIPTION
---------- ---------------------------------------- -----------------------------------------------------------------
AB         Auto BMR                                 A general class of locks used by auto BMR for various purposes
AC         Application Continuity                   Synchronizes new service activation
AD         ASM Disk AU Lock                         Synchronizes accesses to a specific ASM disk AU
AE         Edition Lock                             Prevent Dropping an edition in use
AF         Advisor Framework                        This enqueue is used to serialize access to an advisor task
AG         Analytic Workspace Generation            Synchronizes generation use of a particular workspace
AH         ASM Relocation Lock High                 Protects locked extent pointers during ASM file relocation
AK         GES Deadlock Test                        Lock used for internal testing
AM         ASM Enqueue                              ASM instance general-purpose enqueue
AO         MultiWriter Object Access                Synchronizes access to objects and scalar variables
AP         SPM Autopurge                            This enqueue is used to serialize the purging of SQL plan baselines
AQ         Queue Partitioning local enqueue         Synchronizes partition operations on queue table within instance
AR         ASM Relocation Lock                      Protects locked extent pointers during ASM file relocation
AS         Service Operations                       Synchronizes new service activation
AT         Alter Tablespace                         Serializes 'alter tablespace' operations
AU         DBKR                                     This enqueue is used to serialize ADR purge operation
AV         ASM volume locks                         id1 is for persistent DG number locking. id2 is for other volume serialization
AW         Analytic Workspace                       Synchronizes access to Analytic Workspace resources
AY         KSXA Test Affinity Dictionary            Affinity Dictionary test affinity synchronization
AZ         Emon-SRVNTFN_Q Create                    Synchronize creation of AQ_SRVNTFN_Q among emon slaves
BA         non durable sub bmap alloc               Synchronizes access to globl Bitmap Alloc
BB         Global Transaction Branch                2PC distributed transaction branch across RAC instances
BC         BA Container                             Backup Appliance Container
BE         Critical Block Allocation                Lock used to serialize allocation of critical blocks
BF         BLOOM FILTER                             Synchronize access to a bloom filter in a parallel statement
BI         BA Contained File Identification         Backup Appliance Contained File Identification
BM         clonedb bitmap file access               synchronizes clonedb bitmap file operations
BO         DRM Banned-Object List                   Coordinates dynamic remastering banned-object list
BR         Backup/Restore                           Lock held by a backup/restore operation to allow other operations to wait for it
BS         Backup/Restore spare enq                 KRB space usage
BU         Buddy Instance Context                   synchronizes access to Recovery Set constructed by RMS0
BV         BA Group Rebuild/Validate                Backup Appliance Container Rebuild/Validate
BZ         BA Contained File Resize                 Backup Appliance Contained File Resize
CA         Calibration                              Lock used by IO Calibration
CB         CBAC Master Lock                         Synchronizes accesses to the CBAC roles cached in KGL
CC         Column Key                               Serializes Column Encryption Key Cache
CF         Controlfile Transaction                  Synchronizes accesses to the controlfile
CI         Cross-Instance Call Invocation           Coordinates cross-instance function invocations
CL         Label Security cache                     Synchronizes accesses to label cache and label tables
CM         ASM Instance Enqueue                     ASM instance and gate enqueue
CN         KTCN REG enq                             Enqueue held for registrations for change notifications
CO         KTUCLO Master Slave enq                  Enqueue held for determining Master Slaves
CP         Pluggable Database                       Coordinate pluggable database operations
CQ         Cleanup querycache registrations         Serializes access to cleanup client query cache registrations
CR         Reuse Block Range                        Coordinates checkpointing of block range reuse
CT         Block Change Tracking                    A general class of locks used by change tracking for various purposes
CU         Cursor                                   Recovers cursors in case of death while compiling
CX         TEXT: Index Specific Lock                Index Specific Lock on CTX index
DA         Instance DP Array                        Slave Process Spawn reservation and synchronization
DB         DbsDriver                                Synchronizes modification of database wide supplementallogging attributes
DD         ASM Local Disk Group                     Synchronizes local accesses to ASM disk groups
DE         Planned Draining RAC enqueue             Enqueue to serialize draining structure updates
DF         Datafile Online in RAC                   Enqueue held by foreground or DBWR when a datafile is brought online in RAC
DG         ASM Disk Group Modification              Synchronizes accesses to ASM disk groups
DI         GES Internal                             Coordinates Global Enqueue Service deadlock detection
DL         Direct Loader Index Creation             Lock to prevent index DDL during direct load
DM         Database Mount/Open                      Enqueue held by foreground or DBWR to synchronize database mount/open or pluggable database open with other operations
DN         Diskgroup number generator               Serializes Group number generations
DO         ASM Disk Online Lock                     Synchronizes disk onlines and their recovery
DP         LDAP Parameter                           Synchronizes access to LDAP parameters
DQ         ASM RBAL doorbell                        Inter-RBAL process metadata invalidation notification
DR         Distributed Recovery                     Serializes the active distributed recovery operation
DS         Database Suspend                         Prevents a database suspend during LMON reconfiguration
DT         Default Temporary Tablespace             Serializes changing the default temporary table space and user creation
DV         Diana Versioning                         Synchronizes access to lower-version Diana (PL/SQL intermediate representation)
DW         In memory Dispenser                      Serialize in memory dispenser operations
DX         Distributed Transaction                  Serializes tightly coupled distributed transaction branches
E          Library Cache Lock 2                     Synchronizes accesses to library cache objects
FA         ASM File Access Lock                     Synchronizes accesses to open ASM files
FB         Format Block                             Ensures that only one process can format data blocks in auto segment space managed tablespaces
FC         Disk Group Chunk Mount                   controls access to an ACD chunk
FD         Flashback Database                       Coordinate flashback database
FE         KTFA Recovery                            Flashback archive Enqueue to serialize recovery
FG         ACD Relocation Gate Enqueue              ACD relocation serialization
FH         Flush Stat                               Serializes flush of ILM stats to disk
FL         Flashback database log                   Synchronize access to flashback database log
FM         File Mapping                             Synchronizes access to global file mapping state
FO         Oracle File System Operation             Synchronize Oracle File System Operations
FP         File Object                              Synchronizes various File Object(FOB) operations
FR         Disk Group Recovery                      enqueue to control ASM recovery
FS         File Set / Dictionary Check              Enqueue used to synchronize recovery and file operations or synchronize dictionary check
FT         Disk Group Redo Generation               controls the privilege to generate redo in a thread
FU         DBFUS                                    This enqueue is used to serialize the capture of the DB Feature           Usage and High Water Mark Statistics
FW         Flashback Writer                         Coordinate RVWR on multiple instances
FX         ACD Xtnt Info CIC                        serialize ACD relocation CIC
FZ         ASM Freezing Cache Lock                  Freezes ASM Cache for a diskgroup
G          Library Cache Pin 2                      Synchronizes accesses to the contents of library cache objects
HC         HSM cache                                Add or Remove from HSM cache
HD         ASM Disk Header                          Serializes accesses to ASM SGA data structures
HM         Hang Manager Test Resource               Resource to Generate Hangs for Hang Manager Testing
HP         Queue Page                               Synchronizes accesses to queue pages
HQ         Hash Queue                               Synchronizes the creation of new queue IDs
HV         Direct Loader High Water Mark            Lock used to broker the high water mark during parallel inserts
HW         Segment High Water Mark                  Lock used to broker the high water mark during parallel inserts
IA         Internal
IC         IOServer Client                          Gets a unique client ID
ID         NID                                      Lock held by a NID operation to allow other operations to wait for it
IF         IOServer File                            Synchronizes file operations
II         IOS Instance fencing lock                Signals fencing of a client in an instance
IK         IOS instance node fencing                Signals cluster/node fencing status
IL         Label Security                           Synchronizes accesses to internal label data structures
IM         Kti blr lock                             Serializes block recovery for an IMU txn
IN         in-memory segment                        Serialize in-memory segment create/drop
IP         PDB Instance State                       Enqueue used to synchronize instance state changes for PDBs
IR         Instance Recovery                        Synchronizes instance recovery
IS         Instance State                           Enqueue used to synchronize instance state changes
IT         In-Mem Temp Table Meta Creation          Synchronizes accesses to a temp object's metadata
IV         Library Cache Invalidation               Synchronizes library cache object invalidations across instances
IZ         INSTANCE LOCK                            Proctects the lock name space used by the instance
JD         Job Queue Date                           Synchronizes dates between job queue coordinator and slave processes
JG         Job Scheduler1                           Synchronizes accesses to the job cache1
JI         Materialized View                        Lock held during materialized view operations (like refresh, alter) to prevent concurrent operations on the same materialized view
JQ         Job Queue                                Lock to prevent multiple instances from running a single job
JS         Job Scheduler                            Synchronizes accesses to the job cache
JX         SQL STATEMENT QUEUE                      synchronize SQL statement queue operations
JZ         Join group dictionary                    Synchronizes modifications to im_domain$ and im_joingroup$
KA         Kernel Service ACL                       Global ACL State (Disabled=0/Enabled=1
KD         Scheduler Master DBRM                    Determine DBRM master
KE         ASM Cached Attributes                    Synchronization of ASM cached attributes
KI         KJCI Serialization Enqueue               Enqueue to Serialize KJCI Cross-Instance Calls
KK         Kick Instance to Switch Logs             Lock held by open redo thread, used by other instances to force a log switch
KL         LOB KSI LOCK                             KSI lock for buffer cache and wgc concurrency
KM         Scheduler                                Synchronizes various Resource Manager operations
KO         Multiple Object Checkpoint               Coordinates checkpointing of multiple objects
KP         Kupp Process Startup                     Synchronizes kupp process startup
KQ         ASM Attributes Enque                     Single Inst Sync of ASM attributes
KR         Enqueue-Delete Rule                      Synchronize delete rule and add rule to ruleset
KT         Scheduler Plan                           Synchronizes accesses to the current Resource Manager plan
KV         KEY VECTOR                               Synchronizes access to a key vector in an IMA query
KZ         ASM:Purge Audit                          Coordinate GEN0 on multiple instances
L          Library Cache Lock 1                     Synchronizes accesses to library cache objects
MC         SGA Log Operation                        Lock held during dml/ddl for a securefile log
MD         Materialized View Log DDL                Lock held during materialized view log DDL statements
MF         SGA Log-Bkt Flush                        Lock held during flushing a log bucket
MG         MGA service                              synchronize MGA service
MH         AQ Notification Mail Host                Lock used for recovery when setting Mail Host for AQ e-mail notifications
MK         Master Key                               Serializes enc$ access
ML         AQ Notification Mail Port                Lock used for recovery when setting Mail Port for AQ e-mail notifications
MM         MMON Management                          MMON AutoTask Management
MN         LogMiner                                 Synchronizes updates to the LogMiner dictionary and prevents multiple instances from preparing the same LogMiner session
MO         MMON restricted session                  Serialize MMON operations for restricted sessions
MP         SGA Log Partition                        Lock held during partitioning an instance log
MR         Media Recovery                           Lock used to coordinate media recovery with other uses of datafiles
MS         Materialized View Refresh Log            Lock held during materialized view refresh to setup MV log
MV         Online Datafile Move                     Synchronizes online datafile move operation or cleanup
MW         MWIN Schedule                            This enqueue is used to serialize the calibration of the           manageability schedules with the Maintenance Window
MX         ksz synch                                Used to synchronize storage server info across all nodes
N          Library Cache Pin 1                      Synchronizes accesses to the contents of library cache objects
OC         Outline Cache                            Synchronizes write accesses to the outline cache
OD         Online DDLs                              Lock to prevent concurrent online DDLs
OE         DLM Enqueue Owner Serialization          Enqueue to serialize access to an Omni Enqueue Owner
OL         Outline Name                             Synchronizes accesses to a particular outline name
OP         Label Security Profile                   Synchronizes access to the ols$profile table
OQ         OLAPI Histories                          Synchronizes access to olapi history resources
OT         TEXT: Generic Lock                       Generic Lock on CTX index
OW         Encryption Wallet                        Serializes wallet initialization and access
PA         Privilege Capture API                    Lock held for modifying or reading a privilege capture
PB         PDB DDL Operations                       Enqueue used to synchronize PDB DDL operations
PC         Enqueue for kzppctxs                     Lock used for accesing kzppctx in SGA
PD         Property Lock                            Serializes property update
PE         Parameter                                Synchronizes system parameter updates
PF         Password File                            Synchronizes accesses to the password file
PG         Global Parameter                         Synchronizes global system parameter updates
PH         AQ Notification Proxy                    Lock used for recovery when setting Proxy for AQ HTTP notifications
PI         Remote PX Process Spawn Status           Communicates remote Parallel Execution Server Process creation status
PJ         DV Policy Admin API                      Lock held for Database Vault policy administration API
PL         Transportable Tablespace                 Coordinates plug-in operation of transportable tablespaces
PM         ASM PST Signalling                       Signals inter-instance access to ASM PST metadata
PP         GES Plug and Play Enqueue                Coordinates Adding Plug and Play Instances
PQ         Queue Ptning global enq                  Synchronizes partitioning operations on queue table accross instances
PR         Process Startup                          Synchronizes process startup
PS         PX Process Reservation                   Parallel Execution Server Process reservation and synchronization
PT         ASM Partnership and Status Table         Gates inter-node synchronization of ASM PST metadata
PV         KSV slave startup                        Synchronizes slave start_shut
PW         Buffer Cache PreWarm                     Coordinates Direct Loads with Prewarmed cache buffers
PX         PDB Recovery Operations                  Enqueue used to synchronize recovery-related PDB operations
PZ         Password File Metadata Cache             Synchronizes changes to the password file metadata cache
Q          Row Cache                                Coordinates updates and accesses to row cache objects
RA         Real-Time ADDM Flood Control             Coordinate Flood Control in RAC
RB         ASM Rollback Recovery                    Serializes ASM rollback recovery operations
RC         Result Cache: Enqueue                    Accessing a result in the result-set cache
RD         RAC Load                                 synchronize update of RAC load info
RE         Block Repair/Resilvering                 Synchronizes block repair/mirror resilvering operations
RF         Data Guard Broker                        Synchronizes broker lock operation involving lock value
RG         Replication Global                       Coordinates instance-wide replication / streams operations
RH         SQLQ Autopurge                           This enqueue is used to serialize the purging of SQL quarantine configurations
RI         Reader Farm SQL Isolation                Reader Farm SQL Isolation
RK         wallet_set_mkey                          Serializes wallet master key rekey
RL         RAC Encryption Wallet Lock               RAC encryption wallet lock
RM         GES Resource Remastering                 Coordinates Global Enqueue Service resource remastering
RN         Redo Log Nab Computation                 Coordinates nab computations of online logs during recovery
RO         Multiple Object Reuse                    Coordinates flushing of multiple objects
RP         Resilver / Repair                        Enqueue held when resilvering is needed or when datablock is repaired from mirror
RQ         Enqueue-Cross SCN                        Synchronize enqueue-dequeue-cross on SCN generation
RR         Workload Capture and Replay              Prevents concurrent invokers of DBMS_WORKLOAD_*
RS         Reclaimable Space                        Lock held by a space reclaimable operation to allow other operations to wait for it
RT         Redo Thread                              Thread locks held by LGWR, DBW0, and RVWR to indicate mounted or open status
RU         Rolling Migration                        Serilized rolling migration operations
RW         Materialized View Flags                  Lock used when creating or readingmaterialized view flags in detail tables
RX         ASM Extent Relocation Lock               Synchronizes relocating ASM extents
RZ         RFS Logminer FLC                         Synchronizes updates to logminer foreign log cache
SA         Purge SRL                                Coordinates access to SRL by RFS and recovery process
SB         LogicalStandby                           Synchronizes Logical Standby metadata operations
SC         System Change Number                     Coordinates system change number generation on multiple instances
SE         Session Migration                        Lock used by transparent session migration
SF         AQ Notification Sender                   Lock used for recovery when setting Sender for AQ e-mail notifications
SG         OLS groups                               Synchronizes access to ols$groups table
SH         Active Session History Flushing          To prevent multiple concurrent flushers
SI         Streams Table Instantiation              Prevents muiltiple streams table instantiations
SJ         KTSJ Slave Task Cancel                   Serializes cancelling task executed by slave process
SK         Shrink Segment                           Serialize shrink of a segment
SL         Serialize Lock request                   Request serialization to LCK0
SM         SMON Serialization                       Lock to check SMON global work in RAC
SN         PDB SGA ALLOCATION                       Synchronize PDB SGA Allocation
SO         Shared Object                            Synchronizes access to Shared Object(PL/SQL Shared Object Manager)
SP         Spare Enqueue 0                          Spare enqueue 0 for one-off backports
SQ         Sequence Cache                           Lock to ensure that only one process can replenish the sequence cache
SR         Synchronized Replication                 Coordinates replication / streams operations
SS         Sort Segment                             Ensures that sort segments created during parallel DML operations aren't prematurely cleaned up
ST         Space Transaction                        Synchronizes space management activities in dictionary-managed tablespaces
SU         SaveUndo Segment                         Serializes access to SaveUndo Segment
SV         Sequence Ordering                        Lock to ensure ordered sequence allocation in RAC mode
SW         Suspend Writes                           Coordinates the 'alter system suspend' operation
SX         Spare Enqueue 1                          Spare enqueue 1 for one-off backports
SY         IM chunk populate                        Lock used to serialize in-memory chunk populates
SZ         IM segment populate                      Lock used to serialize in-memory segment populates
TA         Instance Undo                            Serializes operations on undo segments and undo tablespaces
TB         SQL Tuning Base Existence Cache          Synchronizes writes to the SQL Tuning Base Existence Cache
TC         Tablespace Checkpoint                    Lock held to guarantee uniqueness of a tablespace checkpoint
TD         KTF map table enqueue                    Serializes updates and inserts to the SMON_SCN_TIME mapping table
TE         KTF broadcast                            Serializes broadcasts for flushes to SMON_SCN_TIME
TF         Temporary File                           Serializes dropping of a temporary file
TG         In Memory Temp Object                    access to imcdt global resource
TH         Threshold Chain                          Serializes threshold in-memory chain access
TI         In Memory Temp Object HT                 access to an imcdt object HT
TK         Auto Task Serialization                  Prevents more than one AutoTask Background Slave from being spawned
TL         Log Lock                                 Serializes threshold log table read and update
TM         DML                                      Synchronizes accesses to an object
TO         Temp Object                              Synchronizes DDL and DML operations on a temp object
TP         Runtime Fixed Table Purge                Lock used for fixed runtime table purge and definition
TQ         Queue table enqueue                      Synchronizes access to queue table
TR         Tablespace Rekey                         Coordinates tablespace rekey
TS         Temporary Segment                        Serializes accesses to temp segments
TT         Tablespace                               Serializes DDL operations on tablespaces
TU         TOP UPD                                  Enqueue to serialize updates to topology data
TW         Cross-Instance Transaction               Lock held by one instance to wait for transactions on all instances to finish
TX         Transaction                              Lock held by a transaction to allow other transactions to wait for it
TZ         in-memory                                Serialize in-memory area create/drop
UF         AWR undostat stat flush for PDB          This enqueue is used to serialize undo stat flush per PDB
UL         User-defined                             Lock used by user applications
US         Undo Segment                             Lock held to perform DDL on the undo segment
UT         Transfer Unified Audit Records           Lock held for transfer of unified audit records
V          Library Cache Lock 3                     Synchronizes accesses to library cache objects
WA         AQ Notification Watermark                Lock used for recovery when setting Watermark for memory usage in AQ notifications
WD         AWR mail package retrieval               Serialize retrieving AWR mail package
WE         AWR auto-export                          Serialize auto-export of AWR data
WF         AWR Flush                                This enqueue is used to serialize the flushing of snapshots
WG         Write gather local enqueue               Long term lock on wgc file state
WI         AWR import                               Serialize the import of AWR dump files
WL         Being Written Redo Log                   Coordinates access to redo log files and archive logs
WM         WLM Plan Operations                      Synchronizes new WLM Plan activation
WN         read_write_snapshot                      Synchronizes read write snapshot creation
WP         AWR Purge                                This enqueue handles concurrency between purging and baselines
WR         LNS archiving log                        Coordinates access to logs by Async LNS and ARCH/FG
WS         Logwriter member                         Used by Logwriter to coordinate communication to databases
WT         AWR CDB-Wide Table Lock                  This enqueue serializes CDB-Wide Operation on AWR Table
XB         ASM Group Block lock                     Prevents client diskgroup use during storage reconfiguration
XC         XDB Configuration                        Synchronization access to XDB configuration
XD         Auto Online Exadata disks                Serialize Auto Management of Exadata disks
XH         AQ Notification No-Proxy                 Lock used for recovery when setting No Proxy Domains for AQ HTTP notifications
XK         GES Test-Lock for KSIRESTXDV             Lock used for internal testing
XL         ASM Extent Fault Lock                    Keep multiple processes from faulting in the same extent chunk
XM         RM Master Lock                           RMON which process this lock is the Master
XQ         ASM Extent Relocation Enqueue            ASM extent relocation
XR         Quiesce / Force Logging                  Lock held during database quiesce or for database force logging
XY         Internal Test                            Lock used for internal testing
Y          Library Cache Pin 3                      Synchronizes accesses to the contents of library cache objects
ZA         Audit Partition                          Lock held for adding partition to Aud table
ZB         in-memory TS                             Serialize in-memory tablespace create/drop
ZC         IM FastStart Admin                       Lock used to serialize in-memory FS tasks
ZD         IM FastStart CU                          Lock used to serialize in-memory FS CU
ZF         FGA Partition                            Lock held for adding partition to Fga table
ZG         File Group                               Coordinates file group operations
ZH         Compression Analyzer                     Synchronizes analysis and insert into compression$, prevents multiple threads analyzing the same table during a load
ZL         Foreign Log Maintenance                  Synchronizes updates to foreign log metadata by LogMiner reader and RFS processes
ZP         Private Temp Table synchronize           Synchronizes add/remove/read of PTT-GTT mapping
ZQ         quiesce enq                              Serialize SMU create and load quiesce
ZR         ZDLRA Server                             Lock held by a recovery server operation to allow other operations to wait for it
ZS         Spillover Audit files                    Lock held for exclusive access on a Spillover audit file
ZX         repopulation file access                 synchronizes file operations during repopulation
ZZ         Global Context Action                    Lock held for updating Global context hash tables