[ Thanks to An Anonymous Reader for
this link. ]
“You can rarely compensate at a higher level for delays
introduced by a lower level, so if you try to solve variability
only at the application level, you may merely shift JVM or OS
delays around without solving the real problem. Fortunately, the
latencies for lower levels tend to be relatively shorter than the
ones at higher levels, so only if your requirement for reducing
variability is extremely high do you need to look lower than the
JVM or the OS. If your requirements aren’t quite so high, you can
probably afford to focus your efforts at the JVM level and in your
application.”