Hello Holger, 2010/8/14 Holger Hoffstaette <[email protected]>: > On Fri, 13 Aug 2010 12:57:22 +0200, Lars Fischer wrote: > > >From http://logback.qos.ch/manual/appenders.html#OutputStreamAppender: > > "Given the structure of current hard drives and performance tests we have > conducted, it appears that turning off immediate flushing or buffering of > character to byte conversions have rather small impact on performance. As > such, as of logback vesion 0.9.19, the ImmediateFlush, BufferedIO and > BufferSize properties have been removed without replacement."
Sorry, I missed this part of the docu. > I got curious and indeed it seems that the underlying file stream > implementation does no buffering, presumably to allow for recovery. > However by default it does not fsync on every event, so even though you > pay the OS system call and file locking (!) overhead, the OS/drive etc. > will likely still buffer anyway. In my experience buffering at least the > usual 4KB (pagesize) before writing can help a lot; log event output is > typically a lot shorter than that. > > Interestingly I remember from a few years back that *some* people with > lots of logs on high-traffic web sites sometimes got better throughput > from unbuffered writes (contrary to everybody's expectation), whereas > most others said buffering was absolutely necessary and a great > improvement. Hmm, looks like I have to drop this feature, when switching to logback. Thank you for the hint! Regards, Lars _______________________________________________ Logback-user mailing list [email protected] http://qos.ch/mailman/listinfo/logback-user
