DEFINE (Temporary Disk)
Authorization
Privilege Class: G
Purpose
Use DEFINE (temporary disk) to increase virtual workspace by attaching temporary disks to your virtual machine. A temporary disk is private (cannot be shared by another virtual machine).
Operands
- T2314, T2319, or T3310
- All above DASD are accepted for compatibility but result in a message indicating that the temporary disk is not defined because space is not available.
- T3380, T3390, T9336, or TFB-512
- All above DASD add a temporary virtual disk to your virtual machine configuration. The 4 digits following the T correspond to the virtual device type. TFB-512 indicates that any supported FBA device is acceptable.
- AS vdev
- vdev
- is the virtual device number of the temporary disk you are defining.
- CYL ncyl
- ncyl
- is the size of this temporary disk in cylinders (valid only for CKD and ECKD disks).
- BLK nblk
- nblk
- is the size of this temporary disk in blocks (valid only for FBA disks).
Usage Notes
- Temporary disk space is assigned from a pool of DASD resources; therefore, you should always format your temporary disk space before you use it.
- The temporary disk may be slightly larger than the size requested because of CP's implementation of system temporary disk space management.
- Using ICKDSF is the preferred method for formatting a DASD device if it is to be used by CP (such as an IPL device). The CMS FORMAT command should be used to format a DASD device if it is to be used as a CMS disk.
- Temporary disks created with this command have cache access if they are on a cached control unit.
- A minidisk, including a temporary disk, is not eligible for minidisk cache if it has been defined with greater than 32767 cylinders. This does not apply to FBA devices. It applies only to ECKD devices.
- If you define a temporary disk as virtual device number 192, the following special rules apply
when you IPL CMS:
- If 192 is unformatted, CMS formats it and accesses it as file mode D.
- If 192 is CP-formatted, CMS reformats it for CMS use and accesses it as file mode D.
- If 192 is CMS-formatted and accessed as a file mode other than D, CMS reaccesses it as file mode D.
When CMS accesses a 192 minidisk as file mode D, any minidisk or SFS directory already accessed as D is released.
- For more information, see Usage Notes.
Responses
DASD vdev DEFINED confirms the definition of the
temporary disk.Messages
For the list of general messages for the DEFINE command, see Messages.
