Differences between openJDK and oracleJDK

[Luan Cestari]

Hi everybody,

One thing that I notice a weird behavior is using FlameGraph (
http://isuru-perera.blogspot.com.br/2015/07/java-cpu-flame-graphs.html
http://www.brendangregg.com/blog/2015-11-06/java-mixed-mode-flame-graphs.html
  http://techblog.netflix.com/2015/07/java-in-flames.html   ) . It seems
that OpenJDK doesn't have all the debug info so it could use tools like
Flame Graph to display the each frame of the stack in a human readable way,
not just the memory address.

I talked about this issue with one of the maintainers of tools like Flame
Graph ( https://github.com/jrudolph/perf-map-agent/issues/39 ) and we
couldn't find a way to resolve this issue and I think it something on the
OpenJDK or the OpenJDK providers (for example, the one that built, package
and make the RPM available for Fedora RPM repository).

What do you think guys? Do you have the same issue?

Kind regards,
Luan

On Wed, 21 Sep 2016 at 11:17 Wang Weijun <weijun.wang at oracle.com> wrote:

>
> > On Sep 21, 2016, at 5:06 AM, Bradford Wetmore <
> bradford.wetmore at oracle.com> wrote:
> >
> >
> >
> > On 9/19/2016 8:04 AM, Steffen Heil (Mailinglisten) wrote:
> >> Hi
> >>
> >>
> >> I have problems with the following method:
> >>
>  sun.security.x509.AuthorityKeyIdentifierExtension.getEncodedKeyIdentifier()
> >>
> >> It exists in openJDK but it does not exist in oracleJDK.
> >
> > It is there in my OracleJDK build.
> >
> > ls -l
> jdk/modules/java.base/sun/security/x509/AuthorityKeyIdentifierExtension.class
> > -rwxr-xr-x 1 brwetmor Domain Users 6458 Sep 12 14:47
> jdk/modules/java.base/sun/security/x509/AuthorityKeyIdentifierExtension.class
>
> The original mail is about the method missing, not the class.
>
> That said, I also don't think there is any difference between OpenJDK and
> Oracle JDK here.
>
> *Steffen*, how do you find the method is missing? The latest jdk9 is
> modularized so you cannot call internal method like before. Is that the
> reason? Can you show the compilation or runtime error?
>
> Thanks
> Max
>
> >
> > There's been a couple of followups points that I won't repeat:
> >
> >> So I have the following questions:
> >> - Are the jsse-Implementations of both JDKs independent?
> >
> > There is no difference in the Oracle and OpenJDK JSSE implementation.
> They are the same.  That said, other distributions which derive from
> OpenJDK (e.g. IcedTea or Linux distros) may have differences, but that is
> outside my knowledge area.  If you build OpenJDK from the source, the
> binaries of JSSE in OpenJDK and OracleJDK will be the same.
> >
> > Brad
>
>