DCMT VARY STORAGE

DCMT VARY STORAGE changes the size of the storage cushion for a specified storage pool. Additionally, it varies the threshold for CA ADS relocatable storage.
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DCMT VARY STORAGE changes the size of the storage cushion for a specified storage pool. Additionally, it varies the threshold for CA ADS relocatable storage.
This article describes the following information:
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Syntax
►►─── DCMT ─┬───────────────────┬─────────────────────────────────────────────►             └─ 
broadcast-parms
 ─┘  ►─── Vary STOrage POOl 
storage-pool-number
 ──────────────────────────────────►  ►─┬─ CUshion 
cushion-size
 ───────────────────────┬───────────────────────────►◄    └─ RElocatable THreshold 
threshold-percentage
 ─┘
Parameters
  • broadcast-parms
    Indicates to execute the DCMT command on all or a list of data sharing group members.
    For more information about broadcasting and
    broadcast-parms
    syntax, see the section How to Broadcast System Tasks.
  • storage-pool-number
    The numeric ID, in the range 0 through 255, of a storage pool defined at system generation time, whose cushion size is to be varied.
  • CUshion
    Varies the number of 1K blocks of storage in the storage cushion.
  • cushion-size
    The new cushion size, in the range 1 through 32,767 blocks. DC/UCF rounds the specified size down to the nearest multiple of 4.
    Thus, if you specify a cushion size of 13, the actual cushion size is 12 blocks.
  • RElocatable THreshold
    Specifies a new relocatable storage threshold. Relocatable storage currently is used only by the CA ADS run-time system. The following CA ADS resources are relocatable:
    • Currency blocks
    • CA ADS terminal blocks (OTBs) and OTB extensions
    • Variable dialog blocks (VDBs)
    • Run-unit lock tables
  • threshold-percentage
    An integer in the range 0 through 100.
    Threshold-percentage
    specifies how full the storage pool must become before relocatable storage is written to the scratch area (DDLDCSCR) across a pseudo-converse.
    A value of 0 directs the system always to write relocatable storage to the scratch area across a pseudo-converse. A value of 100 directs the system never to write across a pseudo-converse.
More Information
  • For more information about defining storage pools, see documentation of the STORAGE POOL and XA STORAGE POOL statements in the
    Administrating section
    .
  • For more information about displaying information about storage pools, see the sections DCMT DISPLAY ALL STORAGE POOLS and DCMT DISPLAY ACTIVE STORAGE.
  • For more information about relocatable storage thresholds, see the
    Administrating section
DCMT VARY STORAGE Usage
Establishing the Cushion Size
  • For the primary storage pool (that is, storage pool 0), the cushion size is initially established at system generation time by the CUSHION parameter of the SYSTEM statement.
  • For the secondary storage pools 1 through 127, the cushion size is initially established at system generation time by the CUSHION parameter of the STORAGE POOL statement
  • For the secondary storage pools 128 through 254, the cushion size is initially established at system generation time by the CUSHION parameter of the XA STORAGE POOL statement
Tuning Relocated Resources
Relocating storage improves use of the storage pool but also increases I/O to the scratch area. You use the RELOCATABLE THRESHOLD option to fine-tune how often resources are relocated.
Establishing Relocatable Thresholds
You use the system generation ADSO statement to establish whether CA ADS resources are relocatable. You specify the initial relocatable thresholds for storage pools when you define the pools at system generation time.
Example DCMT VARY STORAGE
DCMT VARY STORAGE POOL
      VARY STORAGE POOL 128 CUSHION 256 IDMS DC264001 V105 USER:JSMITH   STORAGE CUSHION VARIED FROM 00128 TO00256