c99df3c4_nce_Guide___Configuring_Apache__Description
[Directive] JkLogStampFormat [Description] 
The Tomcat Connector module date log format, using an extended strftime syntax. This format will be used for the time stamps in the JkLogFile. The maximum length of the format is 63 characters. Starting with version 1.2.24 of mod_jk you can also use %Q for adding milliseconds to the log and %q for microseconds. These conversion specifiers are an extension to strftime. They will only work on platforms with a gettimeofday() function. You can use %Q and %q only once in the pattern and also not both together in the same pattern. The default value is "[%a %b %d %H:%M:%S %Y] " and beginning with version 1.2.24 on platforms with a gettimeofday() function it is "[%a %b %d %H:%M:%S.%Q %Y] ".
The Apache Tomcat Connector - Reference Guide - Configuring Apache
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