commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "nicolas de loof" <nico...@apache.org>
Subject Re: [monitoring] timing precision : ms or ns ?
Date Fri, 01 Feb 2008 16:16:15 GMT
on java < 5 backport-util-concurrent is required to provide System.nanotime()


I've no idea of the result of such a bench on other JVM / architectures.
I'll try it on some of my corporate servers (solaris / linux ...)

Having two timing modes would be a solution as you proposed.

2008/2/1, Siegfried Goeschl <siegfried.goeschl@it20one.at>:
>
> Hi Nicolas,
>
> a few thoughts
>
> +) I use dynamic proxies together with JAMon to measure the execution
> time of method invocations - ns would make a lot of sense here
> +) the execution times also depend on you JVM since you are using JRockit
> +) and finally it depends how often you start/stop a monitor
> +) retrotranslator will fail badly since System.nanotime() was
> introduced with Java 1.5
>
> Maybe the decision can be deferred until creating a monitor - the user
> decides whether to use ms or ns?
>
> Cheers,
>
> Siegfried Goeschl
>
> nicolas de loof wrote:
> > Hello,
> >
> > For commons-monitoring my first intent was to use System.nanotime() to
> > compute code performances. A simple bench [1] demonstrates that
> > System.currentTimeMillis is FAR quicker to return current time (on my
> > windows box [2]) :
> >
> > nanoseconds precision may be usefull for profilers, but is it for
> monitoring
> > purpose ?
> >
> >
> >
> > [1] 10000000 time (System.nanoTime() ) vs (System.currentTimeMillis()) :
> >
> > D:\projets\apache\trunks-sandbox\monitoring\target>java -server -cp
> > .\test-classes
> > org.apache.commons.monitoring.bench.CurrentTimeMillisVsNanoTime
> >  nanotime took          : 4683052742ns
> >  currentTimeMillis took : 26907938ns
> >
> > [2]
> > D:\projets\apache\trunks-sandbox\monitoring\target>java -version
> > java version "1.6.0"
> > Java(TM) SE Runtime Environment (build 1.6.0-b105)
> > BEA JRockit(R) (build R27.2.0-131-78843-1.6.0-20070320-1457-windows-ia32
> ,
> > compiled mode)
> >
> >
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
> For additional commands, e-mail: dev-help@commons.apache.org
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message