HP XP P9500 User Manual page 94

4. For Inflow Control, specify whether to restrict inflow of update I/Os to the journal volume
(slows delay response to hosts).
For example, you could have a 100 GB-bandwidth data path with three journals using it. If
an important database is saved to a primary volume in one of the journals, with data of lesser
importance in the other journals, you may decide to restrict the Inflow Control for the less
important journals while not restricting control to the important journal.
Yes indicates inflow will be restricted. No indicates inflow will not be restricted.
If Yes is selected and the metadata or the journal data is full, the update I/Os may stop.
5. For Data Overflow Watch, specify the number of seconds for the system to monitor write data
to the journal volume when the journal volume threshold (80%) is reached. Range is 0-600
seconds. Default is 60 seconds.
If Inflow Control is No, Data Overflow Watch is disabled.
6. For Use of Cache, specify whether to store journal data (initial copy or resynchronization data)
in the cache memory on the remote side (restore journal).
- Use: Journal data will be stored in the cache. When there is insufficient space in the cache,
journal data will also be stored into the journal volume. This setting only takes effect on the
journal volumes of RAID-5 or RAID-6.
Not Use: Journal data is not stored in the cache.
- Blank: The current setting of Use of Cache will remain unchanged.
NOTE:
YKRESYNC REVERSE command is used to change a master journal into a restore journal.
7. For Timer Type, specify the type of clock used for consistency time. This option can only be
selected when no journal volume is registered. The selected option must be the same for
primary and secondary systems.
- System, the system clock of the mainframe host is used. The host MVS IOS routine attaches
timestamp information from the time-of-day (TOD) clock to each write I/O operation. The
timestamp is transferred to the primary system at the beginning of each I/O operation.
- Local, the mainframe system clock is not used.
- None is available only when copy direction of the pair is reversed, S-VOL-to-P-VOL. With
None, the mainframe system clock is used.
8. Click Set when finished.
94 Maintaining the system
This setting does not effect master journals unless the Business Continuity Manager