Monitoring in-memory usage

Monitor in-memory usage from within OpsCenter.

Monitor in-memory usage from within OpsCenter. More information about creating or altering a table to use in-memory is available in the DataStax Enterprise documentation DSE In-Memory section.

A metric and an alert are available for monitoring in-memory usage:
  • The In-Memory Percent Used alert is available to configure for DataStax Enterprise nodes. If the in-memory usage exceeds the configured threshold, an alert is fired. Investigate the alert and adjust the memory threshold configuration as appropriate.
  • The In-Memory Percent Used metric is available to add as a separate graph in the dashboard of OpsCenter versions 5.1.2 and later.


A visual cue (an In-Memory label next to the table name) in the Keyspaces area of OpsCenter indicates whether a table uses the In-Memory option. Click Data > Keyspace > Tables:

To view the in-memory usage of a node:

Procedure

  1. In the left navigation pane, click Cluster > Nodes > List View.
  2. Click the node to view its details.
    The details for the node are displayed. The Memory Usage bar graphs indicate System, Heap, and In-Memory Usage. The In-Memory Usage bar graph only appears if the In-Memory option is configured. In version 5.1.2 of OpsCenter, the In-Memory Usage interpretation depends on the DataStax Enterprise version (4.0 to 4.7 and later):
    • For versions 4.7 and later, the In-Memory Usage currently shown reflects all tables. Each in-memory table takes up a portion of the usage and displays as a different slice within the in-memory bar graph, up to the maximum threshold. The remainder of the graph represents free space.
    • For versions earlier than 4.7, the In-Memory Usage shown reflects per table limits in the bar graph. Since there is no maximum value applicable to all tables, the entire bar graph represents the total in-memory used by a table, split into as many sections as there are in-memory tables. Free space is not represented in the bar graph.