B
Enqueue and Lock Names

Introduction

Table B-1 contains a list of the enqueues and locks that are used by Oracle. Locks and Resources are different structures used by Oracle, but sometimes the names are not used correctly. A resource uniquely identifies a certain object that can be locked by different sessions within an instance (Local Resource) or between instances (Global Resource). Each session will have a lock structure on the resource if it tries to lock the resource.

Note: The names of enqueues and locks and their definitions may change from release to release.

Table B-1 Oracle Enqueue and Lock Names

BL, Buffer Cache Management	CF, Controlfile Transaction
CI, Cross-instance Call Invocation	CU, Bind Enqueue
DF, Datafile	DL, Direct Loader Index Creation
DM, Database Mount	DR, Distributed Recovery
DX, Distributed TX	FS, File Set
IN, Instance Number	IR, Instance Recovery
IS, Instance State	IV, Library Cache Invalidation
JQ, Job Queue	KK, Redo Log "Kick"
L[A-P], Library Cache Lock	MR, Media Recovery
N[A-Z], Library Cache Pin	PF, Password File
PI, Parallel Slaves	PR, Process Startup
PS, Parallel Slave Synchronization	Q[A-Z], Row Cache
RT, Redo Thread	SC, System Commit Number
SM, SMON	SQ, Sequence Number Enqueue
SR, Synchronized Replication	SS, Sort Segment
ST, Space Management Transaction	SV, Sequence Number Value
TA, Transaction Recovery	TM, DML Enqueue
TS, Temporary Segment (also TableSpace)	TT, Temporary Table
TX, Transaction	UL, User-defined Locks
UN, User Name	US, Undo Segment, Serialization
WL, Being Written Redo Log	XA, Instance Attribute Lock
XI, Instance Registration Lock	------

BEnqueue and Lock Names

Introduction

Table B-1 Oracle Enqueue and Lock Names

B
Enqueue and Lock Names