Displaying data lookaside facility information

Use the DISPLAY DLF command to display the names of the data sets that are currently being processed as DLF objects (message ISG343I). The ISG343I message output could include allocated Enq/Reserve resources that are not actually DLF objects. See z/OS MVS System Messages, Vol 9 (IGF-IWM).

The complete syntax for the DISPLAY DLF command is:

D DLF 
 
D DLF[,RES={({qname|*}[,rname|,*])}][,HEX][,L={a|name|name-a}]

The parameters are:

RES=(qname[,rname])
A list of major names or resource information for the specified resource(s). Only resources that have at least one requestor are displayed.
Note:
  1. The recommended DISPLAY DLF syntax is: 
    DISPLAY DLF,RES=(SYSZSDO,*)
  2. The parentheses around the resource name(s) in RES=(qname[,rname]) are required.

A resource name must consist of a qname (major name) and can include an rname (minor name). If you specify an asterisk (*) as the last character in the resource name, then the system treats the name as a generic name; the display includes all resources with names that match the portion of the name specified before the asterisk. For example, SYSV* indicates that set of resources whose names begin with SYSV. If you specify major name without a minor name, the system displays just a list of the specified major names of those resources that have requestors. You can specify a generic qname with a specific rname, and conversely, a specific qname with a generic rname.

Specify the HEX operand if you want the resource names to be displayed in EBCDIC and hexadecimal. Use it when you have resource names that contain characters that will not appear on your console (that is, those characters that are not defined in the figure, “;English (U.S) I/O Interface Code for 3277”, which appears in IBM® 3270 Information Display System.)

How you specify qname (the major name) depends on the characters in the name.

qname
If qname only contains characters that are alphanumeric (A–Z and 0–9), national (#, @, and $), and a period (.), specify either:
  • 1–8 alphanumeric characters (a specific major name)
  • 1–7 alphanumeric characters followed by an asterisk (*) (a generic major name)
‘qname’
If qname consists of characters that can be displayed other than alphanumeric, national, or a period (excluding a single quotation mark), use the form ‘qname’. The single quotation marks are required but do not count as part of the length specification for qname. For qname, specify either:
  • 1–8 characters (a specific major name)
  • 1–7 characters followed by an asterisk (*) after the closing single quotation mark (a generic major name)
X‘qname’
If qname contains hexadecimal values or a single quotation mark, specify the name in hexadecimal in the form X‘qname’. The prefix X and the single quotation marks enclosing qname are required but do not count as part of the length specification for qname. For qname, specify either:
  • 2–16 hexadecimal digits (a specific major name)
  • 2–14 hexadecimal digits followed by an asterisk (*) after the closing single quotation mark (a generic major name)
*
If you want a list of the major names of all resources that have requestors, specify ‘*’ to indicate a generic major name.

How you specify rname (the minor name) depends on the characters in the name.

rname
If rname contains characters that are alphanumeric (A–Z and 0–9), national (#, @, and $), and/or a period (.), specify either:
  • 1–52 alphanumeric characters (a specific minor name)
  • 1–51 alphanumeric characters followed by an asterisk (*) (a generic minor name)
‘rname’
If rname consists of characters that can be displayed other than alphanumeric, national, or a period (excluding a single quotation mark), use the form ‘rname’. The single quotation marks are required but do not count as part of the length specification for rname. For rname, specify either:
  • 1–52 characters (a specific minor name)
  • 1–51 characters followed by an asterisk (*) after the closing single quotation mark (a generic minor name)
X‘rname’
If rname contains hexadecimal values or a single quotation mark, specify the name in hexadecimal in the form X‘rname’. The prefix X and the single quotation marks enclosing rname are required but do not count as part of the length specification for rname. For rname, specify either:
  • 2–104 hexadecimal digits (a specific minor name)
  • 2–102 hexadecimal digits followed by an asterisk (*) after the closing single quotation mark (a generic minor name)
*
If you want information on all resources, specify ‘*’ to indicate a generic minor name.
HEX
Resource information is to be displayed in hexadecimal as well as EBCDIC.
L=a, name, or name-a
Specifies the display area (a), console name (name), or both (name-a) where the display is to appear.

If you omit this operand, the display is presented in the first available display area or the message area of the console through which you enter the command.

Example 1:

To display resource information about all resources that have requestors, enter: 
D DLF,RES=(*,*)

Performance implication: This command gives you data about every allocated ENQ/RESERVE resource (including ones that may not actually be DLF objects, see z/OS MVS System Messages, Vol 9 (IGF-IWM)); therefore, there might be a very large display. If this command produces a large amount of output, the command output might fill WTO buffers, and degrade system response time. If the display exceeds the current supply of WTO buffers, an ABEND 09A with reason code 46FA will occur.

Example 2:

To display resource information about all resources whose major name is SYSDSN, enter: 
D DLF,RES=(SYSDSN,*)

Example 3:

To display in EBCDIC and hexadecimal the outstanding ENQ/RESERVES that have a qname of SYSCTLG, enter: 
D DLF,RES=(SYSCTLG,*),HEX
The display includes the hexadecimal representation of the resource name, SYSCTLG, with the hexadecimal representation under it: 
SYSCTLG
EEECEDC
2823337
Parent topic: DISPLAY command