SCHDOPT parameter
Scheduler options
Summary
- Default value
- 0
- Parameter type
- System
- Where set
- On User 0's parameter line or reset by system manager.
- Related products
- All
- Introduced
- Model 204 V6.1 or earlier
Description
Control of the main task scheduler operation and accounting.
- Setting X'10' is relevant to all sites.
- All other settings are relevant only to sites running MP/204.
Valid settings of SCHDOPT, which can be summed, are as follows:
| Setting | Meaning |
|---|---|
| X'00' | No scheduler overhead tracking, no forced offload. This is the default. |
| X'01' | Maintain MAINTASK scheduler overhead. |
| X'02' | Run MP work on an MP subtask even if MAINTASK is not busy. |
| X'04' | Defer page releases until server swap. |
| X'08' | Do server I/O on MP subtask.
Note: As of version 7.6 of Model 204, this setting is disabled (has no effect). |
| X'10' | In CSLICE, check maximum values even if there is an SWAIT. |
| X'20' | Run zIIP work on a zIIP subtask even if MAINTASK is not busy. |
| X'40' | Run zIIP work on a zIIP subtask even if MP subtasks are not busy. |
| X'80' | Allow server swapping to be offloaded to zIIP processors. If you have SCHDOPT=80 set, then you probably want to set SCHDOPT1=01.
Note: As of version 7.6 of Model 204, SCHDOPT X'80'and SCHDOPT1 X'01' are disabled (have no effect).
The X'80' setting is only valid when CCASERVR is in memory (servers swapped into memory). If you set SCHDOPT INDICATION OF SERVER SWAPPING DONE BY ZIIP IS ONLY VALID WHEN CCASERVR IS IN MEMORY Initialization then continues. |