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

Usage Notes
Responses
Examples
low
is the low value of the I/O priority range. It must be a number from 0 to 255.
high
is the high value of the I/O priority range. It must be a number from 0 to 255
and greater than or equal to the low value. If not specified, the high value is
equal to the low value.
1. The initial I/O priority settings for a user can be specified by the IOPRIORITY
statement in the user’s directory entry. If an IOPRIORITY statement is not found
and LPAR I/O Priority Facility is enabled, LOGON processing requests
RELATIVE I/O priority range with a low value of 0 and a high value of 0. The
user’s effective range is computed based on the I/O priority range available to
CP.
2. The I/O priority settings of a user can be displayed by the QUERY IOPRIORITY
command. For more information on this command, see “QUERY IOPRIORITY”
on page 831.
Response 1:
To set I/O priority of user USER1 to an absolute range with a low value of 3 and a
high value of 3, enter the following:
set iopriority user1 abs 3
Command complete
1. Suppose a user requests a RELATIVE I/O priority range of 40 to 100, and the
I/O priority range available to CP is 0 to 15. For relative ranged, the maximum
I/O priority range (0–255) maps proportionately onto the range available to CP
with the highest I/O priority mapping directly to the highest value available to
CP. The following table shows how the entire range of relative I/O priorities map
onto the range available to CP:
Relative Value Maps to CP’s Priority
0 to 16 0
17 to 33 1
34 to 50 2
51 to 67 3
68 to 84 4
85 to 101 5
102 to 118 6
119 to 135 7
136 to 152 8
153 to 169 9
170 to 186 10
187 to 203 11
204 to 220 12
221 to 237 13
SET IOPRIORITY
Chapter 2. CP Commands 1261