NLog File target and keepFileOpen flag
===

A FileTarget object in NLog has a property (bool) called "keepFileOpen".
By default this property is set to false, meaning that each log event will open the file, write in the file and close the file.

The hit in performance is huge, so I specified "keepFileOpen" to true, instead of false, meaning that the file will be opened only once.

Does anybody has an idea (or just know) why this property is by default set to "false", incuring a HUGE performance hit on logging ?

Is there any scenarios where setting this property to true can cause issues (which would therefore make sense to default it to "false").

Thanks !

**EDIT**

Performance measurements for basic layout, writing 100000 events to the logger :

 - keepFileOpen = false (default) : ~ 101 sec
 - keepFileOpen = true : ~ 1 sec

