Circular Buffer

The circular buffer supplements the post-mortem dump and the cyclic and single shot measurements. Use the circular buffer if you want an overview of the behavior of the DUT, or an overview of specific conditions in a certain time range e.g., before a post-mortem dump is triggered. The circular buffer provides a way to find out what initiated the situation that caused the post-mortem dump.

The circular buffer cyclically saves a set of variables in a separate container in the results file directory of the PCU. If a connection to the testXplorer is configured, you can upload to the data storage of the testXplorer. After a configurable time, the old values are overwritten by the current ones so the used disk space does not increase indefinitely. You can choose the variables that are saved with which frequency.

You can also configure the following parameters:

  • Number of files (blocks) that can exist at the same time (before the oldest one is overwritten).
  • Recording time span (block length) for a single file (block).
  • Maximum size of the single files (blocks).
  • Appendix to the container name where a manually saved block set is stored.

A new file is opened when either the maximum file size is reached or when the configured recording time is reached. The entire time span for which data are kept in the circular buffer is usually the product of the number of blocks and the block length. If the file size limit is reached before the block length time passes, the recorded time span is reduced and the next file starts.