Graphs
Use this page to view graphs of the number of extents in databases or the percentage of cached pages in the buffer pools for databases.
This type of graph is also called a heat map or a treemap. The graphs are created by using the IBM® ILOG Elixir treemap control.
Interpreting the graph
- Size
- In the graphs, each rectangle within a database represents an object, for example a table or an index. The size of the rectangle indicates the relative size of the object.
- Color
For extents, the color indicates the number of extents as indicated by the legend for the graph. The number of extents can affect the ability of the database server to scan a table rapidly for data. A large number of extents causes the database server to spend extra time finding the data. If a table has a large number of extents, consider defragmenting the table or increasing the size of the extents.
For buffer pools, the color indicates the percentage of pages that are cached as indicated by the legend for the graph. A higher percentage of cached pages can improve performance. Queries run on tables with a high cache percentage are faster than queries run on tables with a low cache percentage. If a table has a low percentage of cached pages and queries are slow, consider increasing the size of the buffer pool.
- Text
- To view the information as text, move the cursor over a rectangle, or in the View list, select Data.