Sep 21st 2014
Locks in Oracle Database
Here are list of all locks available in Oracle database 11.2.0.1.0
Locks in Oracle Database
Here are list of all locks available in Oracle database 11.2.0.1.0
S.No | Type | Description |
1 | WM | Synchronizes new WLM Plan activation |
2 | CI | Coordinates cross-instance function invocations |
3 | PR | Synchronizes process startup |
4 | AK | Lock used for internal testing |
5 | DI | Coordinates Global Enqueue Service deadlock detection |
6 | RM | Coordinates Global Enqueue Service resource remastering |
7 | PE | Synchronizes system parameter updates |
8 | PG | Synchronizes global system parameter updates |
9 | FP | Synchronizes various File Object(FOB) operations |
10 | RE | Synchronizes block repair/mirror resilvering operations |
11 | KD | Determine DBRM master |
12 | KM | Synchronizes various Resource Manager operations |
13 | KT | Synchronizes accesses to the current Resource Manager plan |
14 | CA | Lock used by IO Calibration |
15 | PV | Synchronizes slave start_shut |
16 | SP | Spare enqueue for one-off backports |
17 | FM | Synchronizes access to global file mapping state |
18 | XY | Lock used for internal testing |
19 | AS | Synchronizes new service activation |
20 | PD | Serializes property update |
21 | RU | Serilized rolling migration operations |
22 | MX | Used to synchronize storage server info across all nodes |
23 | SC | Coordinates system change number generation on multiple instances |
24 | CF | Synchronizes accesses to the controlfile |
25 | SW | Coordinates the 'alter system suspend' operation |
26 | DS | Prevents a database suspend during LMON reconfiguration |
27 | TC | Lock held to guarantee uniqueness of a tablespace checkpoint |
28 | PW | Coordinates Direct Loads with Prewarmed cache buffers |
29 | RO | Coordinates flushing of multiple objects |
30 | KO | Coordinates checkpointing of multiple objects |
31 | CR | Coordinates checkpointing of block range reuse |
32 | WS | Used by LogWriter to coordinate communication to standby databases |
33 | WR | Coordinates access to logs by Async LNS and ARCH/FG |
34 | WL | Coordinates access to redo log files and archive logs |
35 | RN | Coordinates nab computations of online logs during recovery |
36 | DF | Enqueue held by foreground or DBWR when a datafile is brought online in RAC |
37 | IS | Enqueue used to synchronize instance state changes |
38 | FS | Enqueue used to synchronize recovery and file operations or synchronize dictionary check |
39 | DM | Enqueue held by foreground or DBWR to synchronize database mount/open with other operations |
40 | RP | Enqueue held when resilvering is needed or when datablock is repaired from mirror |
41 | MV | Synchronizes online datafile move operation or cleanup |
42 | RT | Thread locks held by LGWR, DBW0, and RVWR to indicate mounted or open status |
43 | KK | Lock held by open redo thread, used by other instances to force a log switch |
44 | IR | Synchronizes instance recovery |
45 | MR | Lock used to coordinate media recovery with other uses of datafiles |
46 | BR | Lock held by a backup/restore operation to allow other operations to wait for it |
47 | ID | Lock held by a NID operation to allow other operations to wait for it |
48 | AB | A general class of locks used by auto BMR for various purposes |
49 | MN | Synchronizes updates to the LogMiner dictionary and prevents multiple instances from preparing the same LogMiner session |
50 | PL | Coordinates plug-in operation of transportable tablespaces |
51 | SB | Synchronizes Logical Standby metadata operations |
52 | XR | Lock held during database quiesce or for database force logging |
53 | CT | A general class of locks used by change tracking for various purposes |
54 | RS | Lock held by a space reclaimable operation to allow other operations to wait for it |
55 | FL | Synchronize access to flashback database log |
56 | FD | Coordinate flashback database |
57 | FW | Coordinate RVWR on multiple instances |
58 | TM | Synchronizes accesses to an object |
59 | ST | Synchronizes space management activities in dictionary-managed tablespaces |
60 | TA | Serializes operations on undo segments and undo tablespaces |
61 | TX | Lock held by a transaction to allow other transactions to wait for it |
62 | TW | Lock held by one instance to wait for transactions on all instances to finish |
63 | US | Lock held to perform DDL on the undo segment |
64 | IM | Serializes block recovery for an IMU txn |
65 | TD | Serializes updates and inserts to the SMON_SCN_TIME mapping table |
66 | TE | Serializes broadcasts for flushes to SMON_SCN_TIME |
67 | CN | Enqueue held for registrations for change notifications |
68 | CO | Enqueue held for determining Master Slaves |
69 | FE | Flashback archive Enqueue to serialize recovery |
70 | TF | Serializes dropping of a temporary file |
71 | DT | Serializes changing the default temporary table space and user creation |
72 | HW | Lock used to broker the high water mark during parallel inserts |
73 | TS | Serializes accesses to temp segments |
74 | FB | Ensures that only one process can format data blocks in auto segment space managed tablespaces |
75 | SS | Ensures that sort segments created during parallel DML operations aren't prematurely cleaned up |
76 | SK | Serialize shrink of a segment |
77 | DW | Serialize in memory dispenser operations |
78 | SU | Serializes access to SaveUndo Segment |
79 | TT | Serializes DDL operations on tablespaces |
80 | SM | Lock to check SMON global work in RAC |
81 | SJ | Serializes cancelling task executed by slave process |
82 | SQ | Lock to ensure that only one process can replenish the sequence cache |
83 | SV | Lock to ensure ordered sequence allocation in RAC mode |
84 | HV | Lock used to broker the high water mark during parallel inserts |
85 | DL | Lock to prevent index DDL during direct load |
86 | HQ | Synchronizes the creation of new queue IDs |
87 | HP | Synchronizes accesses to queue pages |
88 | KL | KSI lock for buffer cache and wgc concurrency |
89 | WG | Long term lock on wgc file state |
90 | SL | Request serialization to LCK0 |
91 | ZH | Synchronizes analysis and insert into compression$, prevents multiple threads analyzing the same table during a load |
92 | Q | Coordinates updates and accesses to row cache objects |
93 | DV | Synchronizes access to lower-version Diana (PL/SQL intermediate representation) |
94 | SO | Synchronizes access to Shared Object(PL/SQL Shared Object Manager) |
95 | V | Synchronizes accesses to library cache objects |
96 | E | Synchronizes accesses to library cache objects |
97 | L | Synchronizes accesses to library cache objects |
98 | Y | Synchronizes accesses to the contents of library cache objects |
99 | G | Synchronizes accesses to the contents of library cache objects |
100 | N | Synchronizes accesses to the contents of library cache objects |
101 | IV | Synchronizes library cache object invalidations across instances |
102 | TP | Lock used for fixed runtime table purge and definition |
103 | RW | Lock used when creating or readingmaterialized view flags in detail tables |
104 | OC | Synchronizes write accesses to the outline cache |
105 | OL | Synchronizes accesses to a particular outline name |
106 | CU | Recovers cursors in case of death while compiling |
107 | AE | Prevent Dropping an edition in use |
108 | PF | Synchronizes accesses to the password file |
109 | IL | Synchronizes accesses to internal label data structures |
110 | CL | Synchronizes accesses to label cache and label tables |
111 | MK | Serializes enc$ access |
112 | OW | Serializes wallet initialization and access |
113 | RK | Serializes wallet master key rekey |
114 | RL | RAC encryption wallet lock |
115 | ZZ | Lock held for updating Global context hash tables |
116 | AU | Lock held to synchronize access XML to audit index file |
117 | ZA | Lock held for adding partition to Aud table |
118 | ZF | Lock held for adding partition to Fga table |
119 | DX | Serializes tightly coupled distributed transaction branches |
120 | DR | Serializes the active distributed recovery operation |
121 | BB | 2PC distributed transaction branch across RAC instances |
122 | JD | Synchronizes dates between job queue coordinator and slave processes |
123 | JQ | Lock to prevent multiple instances from running a single job |
124 | OD | Lock to prevent concurrent online DDLs |
125 | DB | Synchronizes modification of database wide supplementallogging attributes |
126 | MD | Lock held during materialized view log DDL statements |
127 | MS | Lock held during materialized view refresh to setup MV log |
128 | PI | Communicates remote Parallel Execution Server Process creation status |
129 | PS | Parallel Execution Server Process reservation and synchronization |
130 | AY | Affinity Dictionary test affinity synchronization |
131 | TO | Synchronizes DDL and DML operations on a temp object |
132 | IT | Synchronizes accesses to a temp object's metadata |
133 | BF | Synchronize access to a bloom filter in a parallel statement |
134 | RC | Accessing a result in the result-set cache |
135 | JX | synchronize SQL statement queue operations |
136 | RD | synchronize update of RAC load info |
137 | KP | Synchronizes kupp process startup |
138 | SR | Coordinates replication / streams operations |
139 | SI | Prevents muiltiple streams table instantiations |
140 | ZG | Coordinates file group operations |
141 | IA | |
142 | JI | Lock held during materialized view operations (like refresh, alter) to prevent concurrent operations on the same materialized view |
143 | AT | Serializes 'alter tablespace' operations |
144 | UL | Lock used by user applications |
145 | CQ | Serializes access to cleanup client query cache registrations |
146 | SE | Lock used by transparent session migration |
147 | TQ | Synchronizes access to queue table |
148 | DP | Synchronizes access to LDAP parameters |
149 | MH | Lock used for recovery when setting Mail Host for AQ e-mail notifications |
150 | ML | Lock used for recovery when setting Mail Port for AQ e-mail notifications |
151 | PH | Lock used for recovery when setting Proxy for AQ HTTP notifications |
152 | SF | Lock used for recovery when setting Sender for AQ e-mail notifications |
153 | XH | Lock used for recovery when setting No Proxy Domains for AQ HTTP notifications |
154 | WA | Lock used for recovery when setting Watermark for memory usage in AQ notifications |
155 | XC | Synchronization access to XDB configuration |
156 | RF | Synchronizes broker lock operation involving lock value |
157 | AW | Synchronizes access to Analytic Workspace resources |
158 | AG | Synchronizes generation use of a particular workspace |
159 | AO | Synchronizes access to objects and scalar variables |
160 | OQ | Synchronizes access to olapi history resources |
161 | IZ | Proctects the lock name space used by the instance |
162 | AM | ASM instance general-purpose enqueue |
163 | FZ | Freezes ASM Cache for a diskgroup |
164 | CM | ASM instance and gate enqueue |
165 | XQ | ASM extent relocation |
166 | AD | Synchronizes accesses to a specific ASM disk AU |
167 | DO | Synchronizes disk onlines and their recovery |
168 | XL | Keep multiple processes from faulting in the same extent chunk |
169 | DG | Synchronizes accesses to ASM disk groups |
170 | DD | Synchronizes local accesses to ASM disk groups |
171 | HD | Serializes accesses to ASM SGA data structures |
172 | DQ | Inter-RBAL process metadata invalidation notification |
173 | DN | Serializes Group number generations |
174 | XB | Prevents client diskgroup use during storage reconfiguration |
175 | FA | Synchronizes accesses to open ASM files |
176 | RX | Synchronizes relocating ASM extents |
177 | AR | Protects locked extent pointers during ASM file relocation |
178 | FR | enqueue to control ASM recovery |
179 | FG | ACD relocation serialization |
180 | FT | controls the privilege to generate redo in a thread |
181 | FC | controls access to an ACD chunk |
182 | FX | serialize ACD relocation CIC |
183 | RB | Serializes ASM rollback recovery operations |
184 | PT | Gates inter-node synchronization of ASM PST metadata |
185 | PM | Signals inter-instance access to ASM PST metadata |
186 | KE | Synchronization of ASM cached attributes |
187 | KQ | Single Inst Sync of ASM attributes |
188 | AV | id1 is for persistent DG number locking. id2 is for other volume serialization |
189 | WF | This enqueue is used to serialize the flushing of snapshots |
190 | WP | This enqueue handles concurrency between purging and baselines |
191 | FU | This enqueue is used to serialize the capture of the DB Feature Usage and High Water Mark Statistics |
192 | MW | This enqueue is used to serialize the calibration of the manageability schedules with the Maintenance Window |
193 | TB | Synchronizes writes to the SQL Tuning Base Existence Cache |
194 | SH | To prevent multiple concurrent flushers |
195 | AF | This enqueue is used to serialize access to an advisor task |
196 | MO | Serialize MMON operations for restricted sessions |
197 | TL | Serializes threshold log table read and update |
198 | TH | Serializes threshold in-memory chain access |
199 | TK | Prevents more than one AutoTask Background Slave from being spawned |
200 | RR | Prevents concurrent invokers of DBMS_WORKLOAD_* |
201 | JS | Synchronizes accesses to the job cache |
202 | XD | Serialize Auto Management of Exadata disks |