SCHDOPT parameter
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. |
| 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 as described in the "Usage Notes" below. The X'80' setting is only valid when CCASERVR is in memory (servers swapped into memory). If you set SCHDOPT=X'80' when CCASERVR is not in memory, the setting X'80' is reset and message 2914 is issued: SCHDOPT INDICATION OF SERVER SWAPPING DONE BY ZIIP IS ONLY VALID WHEN CCASERVR IS IN MEMORY Initialization then continues. |