Application log file

Hello,

Application log can keep trace of user operations and can be used to debug some issues. 

Using database records is not enough fast in my experience, but using either a global field or a variable is not a solution in case of an application crash because data will not be saved.

A possible solution could be using this plugin to write logs to local log file directly.

My questions are:

Will that be fast enough when used intensively to log script instructions and user operations ?

Is the file opened and closed for each write instruction (so that writing are committed, otherwise it will not be useful in case of an application crash) ?

Thanks