RDAREA type | pd_rdarea_warning_point not specified | pd_rdarea_warning_point specified |
---|---|---|
| No message is output. | Segment use has started that makes the segment usage ratio equal to the value specified for all segments of the applicable RDAREA. |
| Segment use has started that makes the segment usage ratio 80%, 90%, or 100% in terms of the relative position of the segment in the last file of the applicable RDAREA. | Segment use has started that makes the segment usage ratio equal to the value specified for all segments of the applicable RDAREA. |
| Segment use has started that makes the segment usage ratio 80%, 90%, or 100% in terms of the relative position of the segment in the last file of the applicable RDAREA. | Segment use has started that makes the segment usage ratio equal to the value specified for all segments of the applicable RDAREA. |
Message output condition | Operand specification value |
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To output a message when segment use has started that makes the segment usage ratio 80%, 90%, or 100% of all the segments in the applicable RDAREA | pd_rdarea_warning_point = 80,90,100 |
To output a message when segment use has started that makes the segment usage ratio 50% or 90% of all the segments in the applicable RDAREA | pd_rdarea_warning_point = 50,90 |
To not output a segment usage warning message | pd_rdarea_warning_point = 0 |
Attribute | Initial status | Opening trigger | Closing trigger | Advantage | Disadvantage |
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INITIAL | Open |
| pdclose command execution | Fast execution from the first SQL. | System startup takes time. |
DEFER | Closed |
| pdclose command execution |
| First access to each RDAREA takes time. |
SCHEDULE | Closed |
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Attribute | Appropriate operation mode |
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INITIAL | HiRDB file system area is opened at system startup and keeps the RDAREA information resident in the memory. The HiRDB file system area is opened also during the initial RDAREA access. Because the RDAREA information is not re-created in this case, high-speed operation can be performed from the first SQL. The initial status of the RDAREA at system startup is open, and this RDAREA status will not change unless an operation command is entered subsequently, except during shift to an error shutdown. This attribute is recommended unless an unusual operation mode is used. When this attribute is used, a closed RDAREA cannot be accessed. |
DEFER | HiRDB file system area is not opened at system startup. Instead, the HiRDB file system area is opened during the initial RDAREA access and the RDAREA information is kept resident in the memory. In the second and subsequent accesses, the processing beyond opening of the HiRDB file system area is not performed, and thus high-speed operations can be achieved. The initial status of the RDAREA at system startup is closed, and each RDAREA is opened during the initial access to that RDAREA. The RDAREA status will not change unless an operation command is entered subsequently, except during a shift to an error shutdown. Specify this attribute if you want to avoid cases in which a large number of HiRDB file system areas are opened concurrently or if you want to shorten the time required for starting HiRDB. When HiRDB is restarted, the RDAREAs to be recovered are opened during recovery processing. When this attribute is used, a closed RDAREA can also be accessed. |
SCHEDULE | HiRDB file system area is not opened at system startup. Instead, after HiRDB startup, the HiRDB file system area is opened during the initial RDAREA access in each transaction and the RDAREA information is kept resident in the memory. When a transaction terminates, the HiRDB file system area opened in that transaction is closed. Thereafter, the processing beyond opening will also be performed during the initial access to an RDAREA whenever the transaction is changed, and thus the workload required for transactions will increase. The initial status of the RDAREA at system startup is closed, and the RDAREA is kept open only during the transaction for the accessed RDAREA. When a transaction terminates, all RDAREAs that were opened in the transaction are closed. If the pdopen command is entered, these RDAREAs can be kept open until they are closed by the next shutdown. It is also possible to use other operation commands to change the status of the RDAREAs. If an error is detected, an error shutdown occurs. This attribute should be specified when it is necessary to compensate for many HiRDB file system areas being opened simultaneously or when it is necessary to reduce the HiRDB system startup time. When HiRDB is restarted, the RDAREAs to be recovered are opened during recovery processing and closed after the completion of the recovery processing. When this attribute is used, a closed RDAREA can also be accessed. |
Facility used | Notes |
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Rapid system switchover facility | A standby unit that is targeted by the rapid system switchover facility has not opened RDAREAs while it is in a standby state. Furthermore, to minimize the time required for system switchover, the standby unit opens only those RDAREAs that are necessary for full recovery when system switchover occurs, and does not open other RDAREAs. Therefore, the RDAREA opening trigger for the standby system cannot be INITIAL. The INITIAL attribute of RDAREAs is changed to DEFER. |
Standby-less system switchover (1:1) facility | To minimize the time required for system switchover, the standby-less system switchover (1:1) facility opens only those RDAREAs that are necessary for full recovery when system switchover occurs, and does not open other RDAREAs. Therefore, the opening trigger for the RDAREAs in the normal BES or alternate portion is as follows:
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Standby-less system switchover (effects distributed) facility | To minimize the time required for system switchover, the standby-less system switchover (effects distributed) facility opens only those RDAREAs that are necessary for full recovery when system switchover occurs, and does not open other RDAREAs. Therefore, when system switchover occurs, the opening trigger for RDAREAs with the INITIAL attribute under the guest BES is changed to DEFER. |
Condition | pd_rdarea_open_attribute_use specification value | |||||
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N | Y | |||||
RDAREA opening trigger | ||||||
INITIAL | DEFER | SCHEDULE | ||||
System switchover facility not used1 | INITIAL | INITIAL | DEFER | SCHEDULE | ||
Standby system switchover facility1 | Rapid system switchover facility not used | |||||
Rapid system switchover facility | Running system | |||||
Standby system | DEFER2 | DEFER | DEFER | SCHEDULE | ||
Standby-less system switchover (1:1) facility1 | Accepting portion (other than the alternate portion of the alternate BES unit) | Running system | INITIAL2, 3 | INITIAL3 | DEFER | SCHEDULE |
Standby system | DEFER2 | DEFER | DEFER | SCHEDULE | ||
Alternate portion | Running system | SCHEDULE2 | SCHEDULE | SCHEDULE | SCHEDULE | |
Standby system | ||||||
Standby-less system switchover (effects distributed) facility1 | Normal start or restart | INITIAL | INITIAL | DEFER | SCHEDULE | |
Restart due to system switchover | DEFER2 | DEFER | DEFER | SCHEDULE |