System.java Development Question

[Claes Redestad]

Hi Max,


On 2018-08-06 17:55, mr rupplin wrote:
>
> Clases, Hello.
>
>
> Firstly thank you for replying.  Of course our goal is to show the 
> strengths in the OpenJDK.
>
>
> Some weeks ago we were working with the ClassFileTransformer as an 
> initial hook for a modest databasing proposal.  We found it to be a 
> dead end.
>
>
> Of course the company has greenlit further work into the area.  We 
> would like to point out JDK did not have any way to hook the malloc 
> sequence at the time.
>

it's great that you're showing an interest in the platform and exploring 
ways to extend/improve it.

It's somewhat coincidental that a lot of work happened in this 
particular area recently.

>
> Please refer us to the technical lay for the Overhead Heap-Profiling 
> reference you refer to; Ok.
>

I thought I already had, but it seems I referred to the initial 
implementation RFE twice. Sorry about that..

The high-level JEP is here: http://openjdk.java.net/jeps/331

It has the high-level overview. From there you can click through to JBS 
details for the JEP, and from there to the implementation.

For historical reference, initial discussion on the proposal here: 
http://mail.openjdk.java.net/pipermail/serviceability-dev/2015-June/017543.html 


There were a couple of code reviews done on open lists, but I think this 
is the final round (and thread): 
http://mail.openjdk.java.net/pipermail/serviceability-dev/2018-May/023668.html

On top of the Low-Overhead Heap Profiling JEP mentioned, JFR was also 
open sourced in time for JDK 11. Perhaps it's memory allocation sampling 
is of interest and a workable alternative.

HTH!

/Claes