z/VM: CP Commands and Utilities Reference - z/VM - IBM

Responses
Note: The guest operator must be able to enter a VARY XSTORE command to
use this procedure. If a guest operator is not available, the guest
operating system must be quiesced before being detached.
6. The amount of Expanded Storage retained for exclusive use for CP paging may
occupy more than one extent or partition of Expanded Storage. The amount
may be specified in 1 MB increments.
7. If RETAIN XSTORE MDCACHE maxM is issued when max is greater than the
current size of the minidisk cache, a gradual reduction in the use of Expanded
Storage for CP paging occurs until the minidisk cache attains the new size. This
does not cause a rapid migration of paging data to auxiliary storage.
8. RETAIN XSTORE MDCACHE performs the same function as SET MDCACHE
XSTORE. Either command can be used to adjust the size of the XSTORE
portion of the minidisk cache. SET MDCACHE STORAGE can be used to adjust
the size of the main storage portion of the minidisk cache.
Response 1:
XSTORE retained, size={nnnnnnnnM} pending={nnnnnnnnM}
{none } {none }
size=nnnnnnnnM
size=none
identifies in megabytes Expanded Storage retained for CP use. If NONE
appears after SIZE, no Expanded Storage was retained.
pending=nnnnnnnnM
pending=none
identifies Expanded Storage waiting for retention. This means that the amount
of Expanded Storage specified was not fully satisfied. When the missing
amount is detached from virtual machines, it becomes retained Expanded
Storage.
Be careful of fragmentation caused by pending retained Expanded Storage. To
avoid fragmentation, enter the RETAIN XSTORE command again with the
amount to be retained equal to the amount given for SIZE in this response. If
none appears after PENDING, no Expanded Storage was retained.
Response 2:
XSTORE MDC retained min=nnnnnnnnM [(nnnnnnnnnM pending)],
max=nnnnnnnnM [(nnnnnnnnnM pending)]
RETAIN XSTORAGE/XSTORE
min=nnnnnnnnM
indicates the current minimum value for the XSTORE portion of the minidisk
cache. The value can be from 0 to 16777216. This may change as the CP
partition size changes.
(nnnnnnnnM pending)
identifies the amount by which the specified value exceeds the current CP
partition size. This means that the minimum/maximum amount of Expanded
Storage for MDC could not be fully satisfied. When the missing amount
becomes available to CP, it is added to the minimum/maximum MDC size value.
This data is shown only if the pending amount is not equal to zero.
max=nnnnnnnnM
indicates the current maximum value for the XSTORE portion of the minidisk
cache. The value can be from 0 to 16777216. This may change as the CP
partition size changes.
Chapter 2. CP Commands 1175