Creating a Memory Store

Create a memory store to retain the state of continuous queries in memory, from the most recent server startup.

Prerequisites
Consult with your system administrator on the type, number, and index values for memory stores, to ensure optimal performance.
Task
  1. In the Visual editor Palette, in Shared Components, click Memory Store.
  2. Select a location in the diagram and click to add the shape.
  3. Connect the memory store to a window.
  4. Specify a name for the store that is unique within its scope for the project or module.
  5. (Optional) Click Set Store Properties properties.gif and modify property values.
    Memory Store Properties
    Property Description
    Index Size Hint (KB) (INDEXSIZEHINT) (Optional) Determines the initial number of elements in the hash table, when using a hash index. The value is in units of 1024. Setting this higher consumes more memory, but reduces the chances of spikes in latency. Default is 8KB.
    Index Kind (INDEXTYPE) The type of index mechanism for the stored elements. Default is Tree.

    Use Tree for binary trees. Binary trees are predictable in use of memory and consistent in speed.

    Use Tree for hash tables, as hash tables are faster, but they often consume more memory.

  6. (Optional) Select Default to make this the default store for the project (or module).
Parent topic: Stores
Related tasks
Creating a Log Store