HP 3000 Manuals HP 3000 Manuals
IO Screen This screen provides I/O information on the data and log buffer pools.To invoke the IO screen, use the i command from the IO subsystem or the /i command from other subsystems. When you issue the SET DBENVIRONMENT command, the counters on this screen are set to zero. Field Definitions REFRESH The screen refresh rate, in seconds. SESSIONS The number of DBEnvironment sessions. per sec The scale used to identify the length of the inverse video bars and the data in the CUR, AVG, and MAX columns. In the example above, the MAX frequency of BUFF ACCESS is 67 per 10.0 seconds. BUFF ACCESS The number of page requests issued to the data buffer pool. DATA DISK RD The number of pages that are not in the data buffer pool at request time. The operating system must fetch these pages, either from the operating system buffer pool or by a physical disk read. DATA DISK WR The number of dirty pages from the data buffer pool that were logically written to disk. LOG BUFF WR The number of records written to the log buffer pool. LOG DISK RD The number of log pages fetched from disk. Unless you have used rollforward recovery, this value is zero. The operating system performs a physical read only if the log page is not found in the operating system buffer pool. LOG DISK WR The number of log pages written from the log buffer pool to disk. The operating system performs a physical write for each log buffer write. CHECKPOINTS The number of checkpoints taken. Checkpoints are performed automatically, when the nonarchive log becomes full, or when you issue a CHECKPOINT command. DATA BUFFER The percentage of pages that are not in the data buffer MISS RATE pool at request time. The percentage is calculated as follows: DATA BUFFER MISS RATE = (DATA DISK RD / BUFF ACCESS) * 100 TOTAL DATA The number of data buffer pages configured. To change BUFFER PAGES the number of data buffer pages, issue the START DBE statement or the SQLUtil ALTDBE command. TOTAL LOG The number of log buffer pages configured. To change BUFFER PAGES the number of log buffer pages, issue the START DBE statement or the SQLUtil ALTDBE command. ARCHIVE MODE Either ON or OFF, to indicate archive or nonarchive logging. Display Conventions The characters displayed in the horizontal bars have special meanings, as explained in the following table. Legend ---------------------------------------------------------------------------------------------- | | | | | Symbol | Corresponding Number | Description | | | | | ---------------------------------------------------------------------------------------------- | | | | | ! | CUR | Represents activity that has | | | | occurred during the most recent | | | | refresh interval. | | | | | ---------------------------------------------------------------------------------------------- | | | | | * | AVG | Designates the average amount of | | | | activity that has occurred since | | | | SQLMON has been attached to the | | | | DBEnvironment. | | | | | ---------------------------------------------------------------------------------------------- | | | | | $ | AVG and CUR | Indicates that the average value | | | | and the value of the most recent | | | | refresh interval are the same. | | | | | ---------------------------------------------------------------------------------------------- | | | | | Full bright inverse | MAX | Designates the maximum amount of | | video | | activity that has occurred since | | | | SQLMON has been attached to the | | | | DBEnvironment. | | | | | ---------------------------------------------------------------------------------------------- Related SET Commands Use the SET REFRESH command to modify the refresh rate of the screen.
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