7.2.4 Operands related to status monitoring (set format) : Hitachi Advanced Database Setup and Operation Guide

Specify this operand to output the warning message KFAA40020-W when the number of concurrent connections approaches the maximum number of concurrent connections specified in the adb_sys_max_users operand.

output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections:

~<integer> ((0 to 100)) <<0>> (percent)

Specify the output threshold for the warning message KFAA40020-W as a proportion of the value specified for the adb_sys_max_users operand (the maximum number of concurrent connections). For example, if you specify 200 for the adb_sys_max_users operand and 90 as the value of output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections, a warning message is output when the number of connections to the HADB server reaches 180 (which is 90% of 200).

If you specify 0 for output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections, the warning message will not be output.

reset-threshold-for-warning-message-output:

~<integer> ((0 to 99)) (percent)

Specify the threshold for resetting the output state of the warning message KFAA40020-W as a proportion of the value specified for the adb_sys_max_users operand (the maximum number of concurrent connections). When the warning message has been output once, HADB registers a state in which the warning message has been output. In this state, the warning message is not output again until the number of connections to the HADB server has fallen below a specific value.

Note

The relationship between the value specified for the adb_sys_max_users_wrn_pnt operand and output of the warning message is as follows:

adb_sys_max_users = 200
adb_sys_max_users_wrn_pnt = 90,70

When the operands are specified in this way, the warning message is output when the number of connections to the HADB server reaches 180 (which is 90% of 200). If the number of connections to the HADB server then falls to 170 before rising again to 180 or more, HADB will not output the warning message again.

However, if the number of connections to the HADB server falls to 140 (70% of 200) or below, the state in which the warning message has been output is reset. This means that subsequently, the warning message will be output again when the number of connections to the HADB server reaches 180 or more.

Notes regarding the threshold for resetting the warning message output state are as follows:

If you do not specify a reset threshold, a value equivalent to output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections - 30 is assumed. If this results in a negative value, 0 is assumed.
Specify the operand so that output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections > reset-threshold-for-warning-message-output. If this condition is not satisfied, the reset threshold specification is invalid (the warning message KFAA40022-W is output). In this case, a value of output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections - 30 is assumed.
If you specify 0 for output-threshold-for-warning-message-regarding-maximum-number-of-concurrent-connections, the reset threshold specification is invalid.

Multi-node function

If you are using the multi-node function, specify the same value for this operand for all of the HADB servers on all nodes.
The warning message KFAA40020-W is output on the master node.

Specify this operand to output the warning message KFAA40021-W when the remaining amount of memory available to the HADB server becomes low.

The value specified for the adb_sys_memory_limit_wrn_pnt operand is only valid if the adb_sys_memory_limit operand is also specified.

output-threshold-for-warning-message-regarding-HADB-server-memory-usage:

~<integer> ((0 to 100)) <<0>> (percent)

Specify the output threshold for the warning message KFAA40021-W as a proportion of the value specified for the adb_sys_memory_limit operand (the maximum amount of memory available to the HADB server). For example, if you specify 64,000 MB for the adb_sys_memory_limit operand and 90 as the value of output-threshold-for-warning-message-regarding-HADB-server-memory-usage, a warning message is output when the memory used by the HADB server reaches 57,600 MB (which is 90% of 64,000).

Important

Immediately after starting the HADB server, execute the adbls -d mem -a command and check the value of TOTAL_USE_PER in the command output. Specify a value for this operand that exceeds the value of TOTAL_USE_PER. TOTAL_USE_PER is the ratio (in percent) of the current memory usage of the HADB server to the value specified in the adb_sys_memory_limit operand.

If you specify a value less than TOTAL_USE_PER, the conditions for outputting the warning message will be met as soon as the HADB server starts. In this case, the warning message is output when the HADB server starts, and no further warning messages are output during HADB operation.

If you specify 0 for output-threshold-for-warning-message-regarding-HADB-server-memory-usage, the warning message will not be output.

reset-threshold-for-warning-message-output:

~<integer> ((0 to 99)) (percent)

Specify the threshold for resetting the output status of the warning message KFAA40021-W as a proportion of the value specified for the adb_sys_memory_limit operand (the maximum amount of memory available to the HADB server). When the warning message has been output once, HADB registers a state in which the warning message has been output. In this state, the warning message is not output again until the memory usage of the HADB server has fallen below a specific value.

Note

The relationship between the value specified for the adb_sys_memory_limit_wrn_pnt operand and output of the warning message is as follows:

adb_sys_memory_limit = 64,000
adb_sys_memory_limit_wrn_pnt = 90,70

When the operands are specified in this way, the warning message is output when the memory usage of the HADB server reaches 57,600 MB (which is 90% of 64,000). Subsequently, if the memory usage of the HADB server falls to 51,200 MB (which is 80% of 64,000) before rising again to 57,600 MB or more, HADB will not output the warning message again.

However, if the memory usage of the HADB server falls to 44,800 MB (70% of 64,000) or less, the state in which the warning message has been output is reset. This means that the warning message will be output again when the memory usage of the HADB server reaches 57,600 MB.

Notes regarding the threshold for resetting the warning message output state are as follows:

If you do not specify a reset threshold, a value equivalent to output-threshold-for-warning-message-regarding-HADB-server-memory-usage - 30 is assumed. If this results in a negative value, 0 is assumed.
Specify the operand so that output-threshold-for-warning-message-regarding-HADB-server-memory-usage > reset-threshold-for-warning-message-output. If this condition is not satisfied, the reset threshold specification is invalid (the warning message KFAA40022-W is output). In this case, a value of output-threshold-for-warning-message-regarding-HADB-server-memory-usage - 30 is assumed.
If you specify 0 for output-threshold-for-warning-message-regarding-HADB-server-memory-usage, the reset threshold specification is invalid.

Multi-node function

The warning message KFAA40021-W might be output on all nodes.

~<integer> ((0 to 86,400)) <<1,800>> (seconds)

Specify, in seconds, the maximum amount of time to wait for the next processing request after having responded to a processing request from an HADB client.

If no processing request is received from the HADB client within this wait time limit, the connection to the HADB client is terminated. If a transaction is being processed, that transaction is rolled back before disconnecting the HADB client.

If 0 is specified for this operand, no upper limit is set for the wait time.

Multi-node function: When master node switchover occurs, the application programs that are connected to the HADB server but that are not performing transactions are disconnected from the HADB server.

~<integer> ((0 to 120)) <<10>> (minutes)

Specify in minutes the no-communication time after which an alive check using the KeepAlive probe starts for the connection established with an HADB client.

Normally, there is no need to specify this operand. By specifying this operand, you can change the OS's KeepAlive control (the no-communication time after which the KeepAlive probe starts).

If there is no response to the KeepAlive probe, the alive check is repeated four times at 30-second intervals. If there is still no response, the connection to the HADB client is cut off.

If 0 is specified for this operand, the alive check using the KeepAlive probe is not performed.

Note: KeepAlive is a function that checks whether a connection is alive based on a response or non-response to a probe packet that is sent at regular intervals. A probe packet is a packet that is sent to check whether a communication line is alive.