[PATCH] JMC-5128/JMC-5149 - Utilize EventThread field in GC Phase Events

Marcus Hirt marcus.hirt at oracle.com
Mon Aug 13 19:59:28 UTC 2018

Hi Joshua,

I agree that the thread field should be added to the phases table. I worry about having a threads table in the beginning of the page, as it moves the focus from GCs to threads. If you are only interested in thread halts in relation to other events in the recording, you should really go to the Application page. Then you see all the halts (for example other vm-operations), and not only the GC-related ones.

You could keep the Thread Activity lane, but for example make it show events for the threads involved in whatever selection you do in the tables above (without having an explicit threads table). 

What do you think?

Kind regards,

From: Joshua Matsuoka <jmatsuok at redhat.com>
Date: Monday, 13 August 2018 at 20:51
To: Marcus Hirt <marcus.hirt at oracle.com>
Cc: <jmc-dev at openjdk.java.net>
Subject: Re: [PATCH] JMC-5128/JMC-5149 - Utilize EventThread field in GC Phase Events

Hi Marcus,

Thanks for the feedback!

I was following the suggestions in the comments/history on https://bugs.openjdk.java.net/browse/JMC-5128 . I think there's value to having the thread lane able to be visualized alongside the rest of the GC information. It's nice being able to see the thread events/activity align with the pause visualization and heap activity. I can also seeing this be useful for users who may have custom events defined, where it may be useful to see these events alongside the heap/gc behaviour.  I noticed as well that the thread activity display on the Java Application page lacks the context menu options to display additional types of events in the visualization. Perhaps if we feel that these changes are unnecessary, I can make an additional patch that could add that functionality to the thread lane on the application page. In either case though, we should probably still add the event thread to the information displayed for pause events.


- Josh

On Mon, Aug 13, 2018 at 11:56 AM, Marcus Hirt <mailto:marcus.hirt at oracle.com> wrote:
Hi Josh,

Thanks for the suggestion! The normal work process is to focus the UI on 
whatever is of interest, and then just go to the Applications view. That way
we end up not having to replicate that functionality on every page.

Can you tell me a little bit more about your use case and how you see this
being used?

(Good initiative! I think you're the first non-Oracle employee attempting to 
improve on the visualization, so kudos!)

Kind regards,

On 2018-08-13, 17:41, "jmc-dev on behalf of Joshua Matsuoka" <mailto:jmc-dev-bounces at openjdk.java.net on behalf of mailto:jmatsuok at redhat.com> wrote:


    This is a patch that addresses JMC-5128 and JMC-5149. Currently the event
    thread field in the GC Phase Events isn't used by the UI. This patch
    accomplishes the following:

    - Adds this field to the phases table.
    - Adds a Thread table similar to the Java Application page which displays
    the threads that the phase events occurred on.
    - Adds a Thread lane to visualize the thread selected by the above table.

    This is a screenshot of the updated UI: https://imgur.com/a/CFQz9G6



    - Josh

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