PRIORITY command

Summary

Privileges

System manager, system administrator, or operator

Function

Assigns a user to a priority class or displays information about priority assignments

Syntax

PRIORITY [usernumber [,LOW | ,STANDARD | ,HIGH]]

or

PRIORITY usernumber [,cur | (cur,min,max)] [,keyword=value]

or

PRIORITY usernumber, CANCEL

Where:

usernumber is the number of the user whose priority is being assigned or displayed.

If specifying...	Then Model 204 lists priority information...
Neither usernumber nor the priority	For all active users (see the format below).
Only usernumber	For only that user.
Both usernumber and the priority	Specified to that user.

• If no further parameters are specified, only usernumber is displayed.

• If further parameters are specified, a comma must separate usernumber as well as the subsequent parameter values.

• cur specifies new current priority for specified user (0-253)

• min specifies the new minimum priority for specified user (1-253)

• max specifies the new maximum priority for specified user (1-253)

• keyword=value is used to change the value of one of the parameters in the table below.

  To change user 8's IOSLICE to 66 and their cur,min,max to 104,80,127, use the following:

  PRIORITY 8,(104,80,127),IOSLICE=66

  To reset user 8's IOSLICE value back to the system default, specify a null value as follows:

  PRIORITY 8,,IOSLICE=,

  Note: keyword=value must be preceded by the value of cur, min, max or by double commas (,,) to indicate that the values do not change. The comma following the equal sign is used to represent a null value.

  PRIORITY command keywords

  Keyword	Meaning
  IOSLICE	CPU milliseconds allowed while user is I/O bound
  CPUSLICE	CPU milliseconds allowed while user is CPU bound
  SLCWAIT	Sleep time in milliseconds when a user reaches minimum priority level.
  SLCMAX	Number of SLCs before CSLICE invoked (max=65545). Declines in this number increase the accuracy of the slice interval. However, CPU overhead increases.

• CANCEL will end the user's current request. The error procedure will be invoked if the user is in a subsystem.

Example

The following example requests priority information about all active users. The SERV column is either a server number or OUT for swapped out. Note that the column labeled MAX below is SLCMAX.

PRIORITY USER USERID P CUR,MIN-MAX SLICE IOSLICE CPUSLIC MAX SLCWAIT SERV CPU 0 NO USERI S 053,032-079 0.000I 0.070 0.100 50 0.00 OUT 0.001 1 BECKETT S 061,032-079 0.000I 0.070 0.100 50 0.00 OUT 0.013 2 LESTER H 127,080-127 0.000I 0.070 0.100 50 0.00 5 0.170 3 MATSUZAK S 061,032-079 0.000I 0.070 0.100 50 0.00 OUT 0.012 4 PENNY H 104,080-127 0.000I 0.070 0.100 50 0.00 1 0.422 5 WAKEFIEL H 114,080-127 0.000I 0.070 0.100 50 0.00 3 0.105 6 VARITEK S 079,032-079 0.000I 0.070 0.100 50 0.00 OUT 0.063 7 YOUKILIS S 079,032-079 0.000I 0.070 0.100 50 0.00 OUT 0.069 8 PEDROIA S 079,032-079 0.000I 0.070 0.100 50 0.00 6 0.133 9 LOWELL S 072,032-079 0.000I 0.070 0.100 50 0.00 OUT 0.032 11 LUGO S 079,032-079 0.000I 0.070 0.100 50 0.00 2 0.112

The following example requests priority information about user number 112:

PRIORITY 112

The following example assigns a HIGH priority to user number 2:

PRIORITY 2, HIGH

Usage notes

The PRIORITY command allows Model 204 resources to be allocated to individual users or applications based upon their relative service requirements. This is done by placing users in one of three priority classes (LOW, STANDARD, or HIGH) or by assigning a number to indicate the user's priority.

In general, HIGH priority users receive prompter service than STANDARD priority users, and STANDARD priority users receive prompter service than LOW priority users. A detailed presentation of priority scheduling is included in Dynamic dispatching.

Once a priority has been assigned, that priority remains in effect until it is changed by another PRIORITY command or until you log out of Model 204.

The output of the PRIORITY command displays the information listed in the following table.

PRIORITY command output formats

Header	Description
USER	User number
USERID	User ID as supplied at login
P	Current priority class. L-Low, S-Standard, H-High, *-Set by PRIORITY Command, Z-Sleeping (priority 0), ? - Priority change in progress
CUR	Current priority
MIN	Minimum priority
MAX	Maximum priority
SLICE	I for I/O bound or C for CPU bound.
IOSLICE	CPU milliseconds allowed while user is I/O bound.
CPUSLIC	CPU milliseconds allowed while user is CPU bound.
MAX	SLCMAX. Number of Stop-Loop-Checks (SLCs) before CSLICE invoked (max=65535).
SLCWAIT	Sleep time in milliseconds, invoked each time a user reaches minimum priority level.
SERV	Server number the user currently occupies. OUT if not in-server.
CPU	Amount of CPU time consumed by this user.