Guidelines for using large log support

The Log and Trace Analyzer provides two methods of loading log resources into the workspace. The default method uses zipped XMI files to persist the imported log data into workspace, and the alternate method, large log support, uses a local or remote database to store the log resources as they are imported into the workspace.

A log resource is active when it is loaded into memory by any action that results in displaying the log resource in a view. The large log support mode should be used when working with active log files whose combined size on import is greater than 4% of the total Java heap size(default size is 512MB). This recommendation is based on tests performed on a Pentium III (1GB RAM, 1GHZ CPU) running the Log and Trace Analyzer.

XMI and large log support can be used together in a single session. However, mixing the two modes of resources may not perform as well as using a single mode operation. Using a combination of the modes may result in performance degradation and excess memory consumption. Follow these guidelines when running with mixed mode of log resources:

  1. All types of correlations are supported when running in large log support mode.
  2. If you have a list of resources and one is an XMI resource, Log actions can only be performed on resources of the same mode, you will be asked to select the mode of resource for the actions to apply and limited to the set of resources of the selected mode. Actions that can trigger a single-mode operation include opening a view, opening a log interaction, or a correlation of mixed resources. As well, opening a monitor, correlation, or a node with mixed resources will result in a single-mode operation. If you need to switch to a different mode of operation, rerun the action again.

Related tasks
Enabling large log support for the Log and Trace Analyzer


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