How to change the underlying buffer size of BufferedOutputStream used by logback's FileAppender?

Question

We are using logback as our logging framework. We noticed that the FileAppender uses ResilientFileOutputStream which is backed by an BufferedOutputStream. We are wondering if there's a way to configure the buffer size of this BufferedOutputStream instance so that we can tune the performance of logback.

Thanks

Answer 1

As i remeber, BufferedOutputStream uses a buf size of 8192 per default. I remember an perfomrance examination paper, where they showed that 8192 is the most performant. It does not make sense to raise the size of more than 8192

Answer 2

This is an interesting bit of information. Looking at the source code, the buffer size is, as you suggest, 8192 by default (http://docs.oracle.com/javase/6/docs/api/java/io/BufferedOutputStream.html). In Java 4, Javadoc indicated that it was 512. The information has disappeared from Javadoc in Java 6 and 7.