High ctree Memory

If the Canister message indicates High ctree Memory, the configured RAM aside for the STC is insufficient for current processing load. Do the following:

  • Review your STC memory settings. See STC memory settings.
  • Identify if this issue has occurred a peak period or is a normal load
  • Identify if there are any reasons why the load may have recently changed. For example, if recent changes to the web application have resulted in large average page sizes or more hits per session, STC processing capabilities may be affected.
  • It may be that there are a high number of sessions in the STC waiting for writing to LTC. See Sessions waiting for archive to disk.

To resolve high ctree memory issues:

  • Review your session timeout settings. The value Session Timeout in the Canister report indicates the current session timeout.
  • Review your session size settings. Three parameters in the Services Controls tab define the limits in size of a session in terms of hits, time, or kilobytes of data.
    • For more information on changing the above settings, see "Configuring the Canister" in the Unica Discover Configuration Manual.
  • You should consider configuring Session Close events to terminate sessions earlier.
  • Acquire more memory for the STC server.

STC memory settings

require-text

In the Canister report

  • In most Discover deployments, the STC begins spooling hits when Memory In Use reaches 80% of the total available memory, as defined in Canister Memory Configuration.
  • Sessions waiting for evaluation (STC) indicates the number of Discover sessions that have been spooled.
  • Freeing up memory: You can review the following configuration settings to make more memory available in the STC for processing hits:
    • Max Ctree Bytes In the Services Controls tab, this setting defines the amount of RAM memory available for the Short Term Canister. It should be evaluated based on other required resources on the Processing Server.
    • Session Size Limits In the Services Controls tab, the following settings define the maximum permitted sizes of sessions, in terms of hits, data, and time. Reducing these size settings may increase the amount of free memory available for processing other hits.
      • Max Hits Per Session
      • Max Size Per Session
      • Max Time Per Session
        Note: The above settings may not be available in standard format. To change them, you may have to edit the Canister configuration in raw format. See "Manage Services WorldView Tab" in the Unica Discover Administration Manual.
    • Number of Hits Processors In the Services Controls tab, you may choose to increase the number of Hit Processors. Some considerations apply. See Hit Processors.