title: Serilog File/RollingFile sink and buffering
body: <p>It <a href="https://github.com/serilog/serilog/blob/dev/src/Serilog.Sinks.File/Sinks/File/FileSink.cs#L94" rel="noreferrer">looks like</a> Serilog File/RollingFile sink flushes stream after each logger call.</p>
  
  <p>Isn't this fundamental performance hit? For example <a href="https://github.com/nlog/NLog/wiki/File-target#asynchronous-logging" rel="noreferrer">Nlog has some kind of AsyncWrapper</a> for queuing log events and writing them in batch'es using background thread. </p>
  
  <p>What are the solutions if I want to minimize latency when using file sink?</p>