684 Chapter 8
Command Definitions SP-Z
TUNE
TUNE
Changes scheduling characteristics of the scheduling subqueues. These characteristics
include base and limit priorities, quantum bounds (min and max), boost property and
timeslice. (Native Mode)
Syntax
TUNE[ minclockcycle] { ;CQ=qinfo ;DQ=qinfo ;EQ=qinfo } [ ... ]
Where qinfo is written in the following form:
[ base [ , [ limit] [ , [min] [ , [max] [ ,DECAY ,OSCILLATE ] ,
[ tslice]]]]]
NOTE Misuse of this command can significantly degrade system operating
efficiency.
PARAMETERS
minclockcycle This parameter is ignored. It appears here for MPE V/E compatibility only.
base An integer from 150 to 255 specifying the priority at which user processes
executing in the CS, DS, and ES scheduling subqueues begin their
Dispatcher transactions. Priority is inversely related to the integer: a
higher-priority process has a lower number. While the full range is
provided for compatibility, avoid setting the base priority between 150 and
152, since user processes running at priorities greater than 152 can
adversely affect system performance.
limit An integer specifying the lowest priority at which a process in the CS, DS,
or ES scheduling subqueues can execute. Priority is inversely related to
the integer: a higher-priority process has a lower number. The limit, which
can range from 150 to 255, must be greater than or equal to the base.
min The minimum quantum is a lower bound for the dynamically calculated
quantum (average transaction time) value. The quantum value
determines the rate of priority decay for processes within the scheduling
subqueue. Values range between 1 and 32767 milliseconds.
max The maximum quantum is an upper bound for the dynamically calculated
quantum (average transaction time) value. The quantum value
determines the rate of priority decay for processes within the scheduling
subqueue. Values range between 1 and 32767 milliseconds. The value of
max must be greater than or equal to the value of min.
DECAY Sets the subqueue to the default decay behavior associated with circular
scheduling subqueues. If set, a process decays normally to the limit priority
and returns to the base priority when the Dispatcher transaction is
complete. DECAY is the default boost property.
