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The following table describes the information displayed in the Main area table.
Table 9- 1 Main area table
| Column | Description |
|---|---|
| Data Partition | <instance>.<database>[.number] |
| Reads & Writes | Total reads and total writes within the selected time frame. |
| Logical Reads | Total logical reads within the selected time frame. |
| Timeouts & Deadlocks | Number of timeouts and number of deadlocks occurred within the selected time frame. |
| Hit Ratio | The buffer cache hit ratio. |
| SQL Types | Total number of Selects, Inserts, Updates and Deletes occurred within the selected time frame. |
| Lock Escalations | Number of lock escalations and exclusive lock escalation occurred within the selected time frame. |
About the Details area
The Details area displays statistics information on the database or database partition selected in the Main area. It has seven tabs: An Overview tab, a Prefetchers tab, a Cleaners tab, a Logging tab, a Package Cache tab, a Sorts tab, and a Locks tab.
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The Overview tab displays information in five views (only first three views are opened by default):
Table 9- 2 Overview tab
| Item | Description |
|---|---|
| Overview | Displays database summed statistics like timeouts and deadlocks. |
| Hit Ratios | Displays an overtime graph of the hit ratios of the database, package cache, and catalog cache. |
| Timeouts & deadlock | Displays overtime graph of timeouts and deadlocks. |
| I/O Activity | Displays overtime stacked-bar graph of the I/O activity of the database. The I/O activity is displayed as an over time stacked bar of synchronic reads and writes, a-synchronic reads and writes, and direct reads and writes. |
| Connections & Agents | Displays an overtime graph of the connections and agents activity. It shows the high water mark of connection, application executing and application connected (idle) as well as associated agents, high water mark of coordinator agents, and high water mark of associated agents. |
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The Prefetchers tab displays information in four views (only the first three views are opened by default):
Table 9- 3 Prefetchers tab
| Item | Description |
|---|---|
| Bufferpools Hit Ratio | This graph displays the bufferpool’s hit ratio over time. It displays separate graphs for database hit ratio, data pages hit ratio, and index pages hit ratio. |
| Physical Reads | This graph displays a stacked bar of the physical reads over time. The stacked bar is divided into synchronic, a-synchronic (for data and for index), and direct reads. |
| Read Response Time | This graph displays overtime line graphs of asynchronous read response time, synchronous read response time and direct read response time. Also displayed is a line graph for the average prefetch wait time. |
| Read Time | This graph displays a stacked bar of read time over time. The stacked bar is divided into synchronic, a-synchronic, and direct read time. |
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The Cleaners tab displays information in four views (only the first three views are opened by default):
Table 9- 4 Cleaners tab
| Item | Description |
|---|---|
| Physical Writes | This graph displays a stacked bar of the physical writes over time. The stacked bar is divided into synchronic, a-synchronic (for data and for index), and direct writes. |
| Cleaners Efficiency | This graph displays overtime line graphs for Victim Page Cleaners Execution [calculated as (bp victim page cleaners triggered) / (bp victim page cleaners triggered+ bp thresh cleaners triggered+ bp log space cleaners triggered)] and synchronous writes to asynchronous writes ratio. |
| Write Response Time | This graph displays overtime line graphs of asynchronous write response time, synchronous write response time, and direct write response time. |
| Write Time | This graph displays a stacked bar of write time over time. The stacked bar is divided into synchronic, a-synchronic, and direct write time. |
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The Logging tab displays information in five views (only the first three views are opened by default):
Table 9- 5 Logging tab
| Item | Description |
|---|---|
| Log Utilization | This graph displays an overtime stacked bar of Primary log used, secondary log used, and log space available. |
| Log Pages Time (ns) | This graph displays a stacked bar of log read time and log write time (in nanoseconds) over time. |
| Commits & Rollbacks | This graph displays a stacked bar of commits and rollbacks over time. |
| Log Buffer Reads - Hits & Misses | This graph displays the log buffer reads ratio between hit and misses. |
| Log Pages Count | This graph displays a stacked bar of log pages reads and log pages writes over time. |
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The Package Cache tab displays information in four views (only the first three views are opened by default):
Table 9- 6 Package Cache tab
| Item | Description |
|---|---|
| Package Cache Hit Ratio | This graph displays the package cache hit ratio, the package cache overflows and the application section hit ratio over time, in a graph with two Y-axis (the left Y-axis is for hit ratio, and the right Y-axis is for overflows). |
| SQL Types | This graph displays a stacked bar of Selects, DMLs and DDLs over time. This graph can be used for findings a correlation between package cache low hit ratio to the high number of DDL. |
| Compile & Recompile | This graph displays a stacked bar of compile time and recompile time over time, as taken from Precise for DB2 collector. This indicates the amount of parsing time the application is spending while running. |
| Dynamic vs. Static | This graph displays a stacked bar of dynamic SQL attempts and Static SQL attempts over time. |
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The Sorts tab displays information in three views:
Table 9- 7 Sorts tab
| Item | Description |
|---|---|
| Sort Heap Overflows (To disk) Ratio | This graph displays the sort ratio { (Sort overflow) / (total sorts)} and hash joins ratio { (hash join overflows) / (total hash joins)} over time. This graph can indicate whether operations are performed on disk (sorts, hash joins), and whether it is needed to adjust the sort heap size. |
| Overflow Count | This graph displays a stacked bar of sort overflows, hash joins overflows, and small hash joins overflows over time. |
| Sort Time | This graph displays the sort time over time. This graph shows data only if the DB2 sort switch is on. |
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The Sorts tab displays information in three views:
Table 9- 8 Locks tab
| Item | Description |
|---|---|
| Timeouts & Deadlock | This graph displays a stacked bar of timeouts and deadlocks over time. |
| Lock Escalations | This graph displays a stacked bar of shared lock escalations and exclusive lock escalations over time. |
| Lock Time (Avg) | This graph displays the average lock time {(lock wait time)/(lock waits)} over time. This graph will have values only in case DB2 Lock Switch is on. |
| Lock List in Use | This graph displays lock list in use over time. |
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- In the Time Frame list, choose the period of time you want to analyze.
- In the Database Partition list, choose the item you want to analyze.
- Check whether you allocated enough log space in the Log Space view. Identify whether secondary log space is used. If so, you probably need to allocate more primary log space.
- Check whether your log read and write time are adequate by looking in the Log Time view. This may indicate whether the current disk is adequate for logging.
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