PING: RFR: 8233373: hs_err should report the location of JFR files

[Markus Gronlund]

Hi,

I have not looked at all the details yet, but from a high level:

You should try to keep JFR specific logic encapsulated in JFR code as much as possible. jfrRepository.hpp and jfrEmergencyDump.hpp are internal modules, so they should not leak out into vmError.cpp.
The jfr.hpp is the external interface for the VM to interact directly with JFR. I would hope that there is only one invocation needed in vmError.cpp, something like JFR_ONLY(Jfr::on_error_reporting(outputStream* out);).
If there are multiple callouts needed to coordinate the layout, then you might need multiple entries in jfr.hpp, but please try to keep them to a minimum.  Pure textual output, such as aligning spaces and # can be printed directly in vmError.cpp of course.

Thanks
Markus


-----Original Message-----
From: Yasumasa Suenaga <suenaga at oss.nttdata.com> 
Sent: den 19 november 2019 02:32
To: hotspot-jfr-dev at openjdk.java.net
Cc: yasuenag at gmail.com
Subject: PING: RFR: 8233373: hs_err should report the location of JFR files

PING: Could you review?

>    JBS: https://bugs.openjdk.java.net/browse/JDK-8233373
>    webrev: http://cr.openjdk.java.net/~ysuenaga/JDK-8233373/webrev.00/


Yasumasa


On 2019/11/01 13:38, Yasumasa Suenaga wrote:
> Hi all,
> 
> Please review this change:
> 
>    JBS: https://bugs.openjdk.java.net/browse/JDK-8233373
>    webrev: http://cr.openjdk.java.net/~ysuenaga/JDK-8233373/webrev.00/
> 
> Since JFR Event Streaming (JEP 349), JFR file in the repository would keep most recently data.
> It is very useful for postmortem analysis. So it helps JVM engineer to acquire them from the user if hs_err log points it.
> 
> 
> Examples:
> 
> * Show JFR repository path:
> ```
> # JFR files might be saved in the repository:
> # /tmp/2019_11_01_11_09_30_3529
> ```
> 
> * Show emergency dump path
> ```
> # JFR data is saved as:
> # /home/ysuenaga/github/garakuta/NativeSEGV/hs_err_pid3807.jfr
> ```
> 
> 
> This webrev passed all tests on submit repo (mach5-one-ysuenaga-JDK-8233373-20191101-0248-6329106)
> 
> 
> Thanks,
> 
> Yasumasa