SCF Reference Manual for the Storage Subsystem (G06.24+, H06.03+)

Storage Subsystem Commands
SCF Reference Manual for the Storage Subsystem—529937-007
14-36
ADD PROFILE Command
FULLCHECKPOINTS { DISABLED | ENABLED | FORCED }
(nondirectory structured files only) specifies when to perform full-block
checkpoints.
For mirrored volumes, FULLCHECKPOINTS is important only if the primary or
mirror disk is not up. In that situation, FORCED or ENABLED can protect the
validity of data written to the disk.
When performing full-block checkpoints, the primary process checkpoints the data
to the backup process before writing to the disk. This action ensures that the data
on the disk is not corrupted even if a hardware freeze or processor halt occurs
during a disk write.
Use FORCED or ENABLED unless data loss is not critical.
HALTONERROR number
specifies whether an internally detected, unrecoverable, disk-process error forces
a halt (code %11500) in the primary processor, backup processor, or both. Forced
processor halts also halt the respective disk process. Forced processor halts can
provide more information at the time of a failure. To force a halt when a failure is
detected, set number to either 2, 3, or 4.
number is one of:
DISABLED Never use a full-block checkpoint to protect the data on the disk.
Using DISABLED maximizes disk performance, but risks
corrupting data blocks on the disk.
ENABLED Use a full-block checkpoint only when serial writes are not being
performed. Use ENABLED on disks that perform parallel writes
and on nonmirrored disks. For more details, see the
SERIALWRITES attribute on page 14-40. (Default)
FORCED Always use full-block checkpoint for disk-write operations.
1 Never halt a processor (default).
No processor halts, and the primary or backup disk process that detects an
unrecoverable disk-process error can go into the STOPPED state, substate
DOWN.
2 Never halt the backup processor.
The primary processor halts, but the backup disk process can go into the
STOPPED state, substate DOWN, if it detects an unrecoverable disk-
process error.