IFCID 172 - Unit of Work - Blocker

This topic shows detailed information about Record Trace - IFCID 172 - Unit of Work - Blocker.

A blocker is a thread that prevents its victim from acquiring its lock. The blocker might be a holder of the lock, or it might be another waiter (that came in before the victim) that is incompatible with the holder's lock.

Note: If the fields PLAN NAME, CORR ID, CONN, and NETWORKID show an asterisk (*), the blocking request was released by the requester or was timed out between the detection and reporting of the deadlock.

Record trace - IFCID 172 - Unit of Work - Blocker

The field labels shown in the following sample layout of Record Trace - IFCID 172 - Unit of Work - Blocker are described in the following section. 


B L O C K E R
PRIMAUTH    : SYSOPR     PLAN NAME : BLOCKPLA     CORR ID : BLOCKCORRID1          CONN ID : BLOCKCON
NETWORKID   : LUWID 1    LUNAME    : XXXXXXXX     OWNING WORK UNIT:      54979    UNIQUENESS VALUE: X'E7E7E7E7E7E7'
MEMBER      : BLOCKMEM   DURATION  :   PLAN       STATE   : PROTECTED SHARE          ACE  :   2
TRANSACTION : HOLDTRANSACTION NAME 00000000001    WS_NAME : HOLD WORKSTATION 1    END_USER: HOLDENDUSER00001
PROGRAM NAME: PGM00001   LOCATION  : LOCATION00000001                             PCKG/COLL ID: COLLECTIONID000001
CONS TOKEN  : X'C1C2C3C4C5C6C7C8'                 STMT ID : X'1234567890123456'            TYPE: X'0000'
STATUS     :  HOLD
QW0172HF: X'12'
PRIMAUTH

The authorization ID of the thread holding the resource.

Field Name: QW0172HB

PLAN NAME

The plan name of the blocker.

Field Name: QW0172HP

CORR ID

The correlation name of the blocker.

Field Name: QW0172HR

CONN ID

The connection ID of the blocker.

Field Name: QW0172HN

NETWORKID
Provides the following information:
  • The logical unit of work identifier of the blocker. The data shown is only valid for distributed threads.
  • The logical unit name of the blocker. The data shown is only valid for distributed threads.
  • The uniqueness value of the blocker. The data shown is only valid for distributed threads.

Field Name: QW0172HL

LUNAME
Provides the following information:
  • The logical unit of work identifier of the blocker. The data shown is only valid for distributed threads.
  • The logical unit name of the blocker. The data shown is only valid for distributed threads.
  • The uniqueness value of the blocker. The data shown is only valid for distributed threads.

Field Name: QW0172HL

OWNING WORK UNIT

The owning unit of work of the blocker.

Field Name: QW0172HO

UNIQUENESS VALUE
Provides the following information:
  • The logical unit of work identifier of the blocker. The data shown is only valid for distributed threads.
  • The logical unit name of the blocker. The data shown is only valid for distributed threads.
  • The uniqueness value of the blocker. The data shown is only valid for distributed threads.

Field Name: QW0172HL

MEMBER

The Db2 member name.

Field Name: QW0172HI

DURATION

The lock duration of the thread blocking the resource.

Field Name: QW0172HD

STATE

The lock state of the thread holding the resource.

Field Name: QW0172HS

ACE

The owning unit of work of the blocker.

Field Name: QW0172HO

TRANSACTION

The transaction or application name that is run.

Field Name: QWHCEUTX

WS_NAME

The end user's workstation name.

Field Name: QWHCEUWN

END_USER

The user ID of the workstation end user. This user ID can be different from the authorization ID used to connect to Db2. This field contains blanks if the client does not supply this information.

Field Name: QWHCEUID

PROGRAM NAME

The name of the program that is in control at the time of the deadlock. It need not be the program that acquired the lock.

Field Name: QW0172Q1

LOCATION

Location of the program that is in control at the time of the deadlock. It need not be the program that acquired the lock.

Field Name: QW0172Q3

PCKG/COLL ID

Package collection ID of the program that is in control at the time of the deadlock. It need not be the program that acquired the lock.

Field Name: QW0172Q2

CONS TOKEN

Consistency token of the program that is in control at the time of the deadlock. It need not be the program that acquired the lock.

Field Name: QW0172Q4

STMT ID

Shows the cached statement ID for the thread holding the resource. This field contains zero (0) if the client does not supply this information.

Field Name: QW0172H9

STMT ID

The holder statement ID.

Field Name: QW0172HZ

TYPE

The holder statement information.

Field Name: QW0172HY

STATUS
The status of the blocker.
WAIT
The blocker is waiting for the resource.
HOLD
The blocker is holding the resource.

Field Name: QW0172H2