Log file correlation

Correlating logs is the process of finding related log records according to a correlation criterion, such as log records having equal timestamps. When two records have the same timestamp, this is indicated graphically and the two records are said to be correlated with each other.

The Log and Trace Analyzer provides the option to display correlations in two ways:

Log interaction diagrams, which display interactions among log records that occur during the execution of an application.
Log thread interaction diagrams, which display interactions among log records that occur on different threads, which participate in the execution of an application.

Here is an example of a log interaction diagram, which happens to be between an access log and an error log:

A column of blue bars and a column of red bars with arrows

The window title displays the view type and the correlation schema used in the format
Sequence Diagram: View name <Correlation schema>
where View name is the Log Interactions view or the Log Thread Interactions view
and the Correlation schema can be a predefined schema format such as Default Time.

Correlations are represented visually by an arrow that points from the source record to the target record. The following are different representations of correlations:

Correlation within a log file in a collapsed node.
Correlation within a log file in an expanded node.
Correlation between log files
Correlation between logs where the source is outside of the current viewing page
Correlation between logs where the target is outside of the current viewing page.