The operands described here are used to select among methods that use one of the following two general approaches:

1. An approach that places a high load on the machine, but provides high performance (for a machine capable of high performance). If the machine's performance capacity is low, CPU usage may approach 100%, posing the risk of degraded OS performance.
2. An approach that places a low workload on the machine, but can ensure standard performance. Stable performance can be achieved with any type of machine.

To minimize risk, the default values for many of these operands are set to use a method that adheres to approach 2.

If your machine's performance capacity is high, you may be able to improve performance (while also increasing the load on the machine) by changing the values specified for these operands. However, if unsuitable values are specified, the CPU usage may approach 100%, posing the risk of degraded OS performance. Thus, you should be careful about changing the specification values for these operands.

Note that these operands are not described in detail here because their specification values are related to the system's complex internal processing. You should refer to the specification guidelines for each operand that are provided in the manual HiRDB Version 8 System Definition.

Table 21-2 lists the operands for tuning the system's internal processing.

Table 21-2 Operands for tuning the system's internal processing

Specification item	Specification condition	Operand
Lock-release detection method	For general UAP execution	pd_lck_release_detect
Lock-release detection interval		pd_lck_release_detect_interval
Processing request queuing method		pd_server_entry_queue
Inter-thread lock sleep method		pd_thdlock_sleep_func
Inter-thread lock sleep time		pd_thdlock_retry_time
Inter-thread spin lock spin count		pd_thdspnlk_spn_count
Global buffer lock-release detection interval	Global buffer lock-release-wait has occurred.	pd_dbbuff_wait_interval
Spin count during global buffer lock release detection		pd_dbbuff_wait_spn_count
Global buffer lock-release detection method	Global buffer is being used.	pd_dbbuff_lock_release_detect
Spin count during global buffer lock-acquisition-wait		pd_dbbuff_lock_spn_count
Interval during global buffer lock-acquisition-wait		pd_dbbuff_lock_interval

Table 21-3 shows the operands for specifying performance during concurrent transaction execution.

Table 21-3 Operands for specifying performance during concurrent transaction execution

Specification item	Specification condition	Operand
Inter-thread lock release notification method	When the execution time must be the same for all transactions that are being executed concurrently.	pd_thdlock_wakeup_lock
Inter-thread lock release detection interval	When the execution times may differ to some extent among the transactions that are being executed concurrently.	pd_thdlock_pipe_retry_interval