2.2.21 Operands related to statistical information

94) pd_statistics = A | Y | N
  • 0904 compatibility mode: <<N>>
Specifies whether collection of the statistics log is to be started when HiRDB starts.
A:
Collect statistical information on system operation (output interval: 1 minute), statistical information on global buffers, statistical information on deferred write processing, and statistical information on database I/O (output interval: 1 minute), when HiRDB starts.
Y:
Collect statistical information on system operation (output interval: 10 minutes), when HiRDB starts.
N:
Do not begin collecting the statistics log at the time of HiRDB startup.
When Y is specified, statistics log information on the system operation of the overall unit only is collected. If information on each server or information other than the statistics information on system operation is needed, the pdstend command must be entered to stop statistical information collection after HiRDB startup has been completed, then the pdstbegin command can be entered to begin collecting statistical information again.
When N is specified, it is still possible to collect a statistics log during HiRDB operation by entering the pdstbegin command.
In addition, if the following conditions are met, statistical information is not collected even if you specify settings to collect statistical information:
  • If the unit that uses the standby-less system switchover (effects distributed) facility and Y is specified for pd_statistics (Statistical information is collected when pd_statistic is A.)
  • If the unit uses the standby-less system switchover (effects distributed) facility and the servers in the unit do not run
  • If all servers in the unit are terminated normally
  • If the unit is a HiRDB parallel server configuration and has only the system manager (No front-end server, back-end server, or dictionary server is placed in the same unit.)
  • If the log application site uses Real Time SAN Replication based on the log-only synchronous method
Specification guideline
We recommend that you specify A to quickly identify the cause of a problem when tuning performance.
Notes
If you specify both pdstbegin and pd_statistics, the pd_statistics setting becomes disabled. To collect statistical information according to the pd_statistics setting, make sure that you do not specify pdstbegin.
95) pd_stj_file_size = maximum-statistics-log-file-size
~<unsigned integer>((64-1000000))<<102400>> (kilobytes)
  • 0904 compatibility mode: <<1024>>
Specifies in kilobytes the maximum size of a statistics log file.
Two statistics log files are provided. When the amount of stored statistics log information reaches the size specified here, the statistics log files are swapped.
Specification guidelines
96) pd_stj_buff_size = statistics-log-buffer-size
~<unsigned integer>((32-512)) <<32>> (kilobytes)
Specifies the statistics log buffer size.
Specification guidelines
The specification guidelines differ depending on the conditions below. If multiple conditions are met, specify the largest value of the values calculated by each formula.
  1. If pcd or obj is specified for the -k option of the pdstbegin command:
    Using the formula below, calculate the statistics log output volume when pcd or obj is specified. Then, specify a value obtained by adding 32 to the calculated statistics log output volume. However, if the value calculated according to this formula exceeds 512, specify 512.
    (a[Figure] 1,024) [Figure] (0.03 [Figure] b)
    a: Statistics log output volume (bytes)
    For details, see C.1 Formulas for determining size of statistics log file (pd_stj_file_size).
    b: pdstend command entry time - pdstbegin entry time (seconds)
  2. If dio is specified for the -k option of the pdstbegin command and everyfile is specified for the -D option:
    Specify the value obtained by adding 32 to the value calculated according to the following formula:
    {(a[Figure] 104) + ([Figure]a[Figure] 16[Figure][Figure] 204)} [Figure] 1024 [Figure] b[Figure] 60
    a: Total number of RDAREA configuration files that are managed by the output target servers in the unit
    b: Output interval specified for the -I option of the pdstbegin command
    However, if the value calculated according to this formula exceeds 512, make sure that you do not specify everyfile for the -D option of the pdstbegin command.
  3. If either condition 1 or 2 is not met:
    Specify 32 (the default value).
97) pd_sqlobject_stat_timing = deallocate | tran
Specifies the timing for collecting statistics on an SQL object buffer. The following table lists and describes the timing for collecting the statistical information and the statistical information that is collected:
No.Timing for collecting statistical informationStatistical information that is collected
deallocatetran
1When the preprocessing results become invalid if the following SQL statements are executed:
  • DEALLOCATE PREPARE statement
  • PREPARE statement
  • EXECUTE IMMEDIATE statement
Preprocessing results that are invalidatedPreprocessing results that are invalidated
2When committedPreprocessing results that are invalidated by commitAll preprocessing results
3When rolled backNot collectedAll preprocessing results
4When the DISCONNECT statement, COMMIT statement with RELEASE specified, or a definition SQL statement is executedAll preprocessing resultsAll preprocessing results
5When the ROLLBACK statement with RELEASE specified is executedPreprocessing results that are not invalidated by rollback when the ROLLBACK statement with RELEASE specified is executedAll preprocessing results
Specification guidelines
Specify tran in the following cases:
  • The preprocessing results become valid beyond the scope of a transaction such as when TRUE is specified for STATEMENT_COMMIT_BEHAVIOR in a holdable cursor or the JDBC driver.
  • The statistics on an SQL object buffer is to be collected during rollback processing.
In any other case, specify deallocate.
Notes
  • When a transaction is decided due to the cancellation of a server process, the statistical information cannot be collected.
  • If TRUE is specified for STATEMENT_COMMIT_BEHAVIOR in a holdable cursor or the JDBC driver, the preprocessing results remain valid beyond the scope of the transaction. Therefore, if deallocate is specified in this operand, the statistics on these SQL object buffers cannot be collected even when the transaction is decided.
  • If TRUE is specified for STATEMENT_COMMIT_BEHAVIOR in a holdable cursor or the JDBC driver, the statistics on an SQL object buffer can be collected only while that cursor is closed.
For details about the holdable cursor and STATEMENT_COMMIT_BEHAVIOR, see the HiRDB Version 9 UAP Development Guide.