IBM Z Software


This portal is to open public enhancement requests against IBM Z Software products. To view all of your ideas submitted to IBM, create and manage groups of Ideas, or create an idea explicitly set to be either visible by all (public) or visible only to you and IBM (private), use the IBM Unified Ideas Portal (https://ideas.ibm.com).


Shape the future of IBM!

We invite you to shape the future of IBM, including product roadmaps, by submitting ideas that matter to you the most. Here's how it works:

Search existing ideas

Start by searching and reviewing ideas and requests to enhance a product or service. Take a look at ideas others have posted, and add a comment, vote, or subscribe to updates on them if they matter to you. If you can't find what you are looking for,

Post your ideas

  1. Post an idea.

  2. Get feedback from the IBM team and other customers to refine your idea.

  3. Follow the idea through the IBM Ideas process.


Specific links you will want to bookmark for future use

Welcome to the IBM Ideas Portal (https://www.ibm.com/ideas) - Use this site to find out additional information and details about the IBM Ideas process and statuses.

IBM Unified Ideas Portal (https://ideas.ibm.com) - Use this site to view all of your ideas, create new ideas for any IBM product, or search for ideas across all of IBM.

ideasibm@us.ibm.com - Use this email to suggest enhancements to the Ideas process or request help from IBM for submitting your Ideas.

Add a new idea Subscribe
Status Delivered
Workspace z/TPF Product Family
Categories z/TPF
Created by Guest
Created on Feb 25, 2020

RELATED IDEAS

(TPFUG/Visa) Need a ways to see both control and location information for RSH buffers

PJ45598 provided support for recoverable system heap. The support allows for a request for recoverable system heap to be serviced from 64 bit system heap if there isn't enough room in the preallocated RSH area.

ZDSHP FIND displays information about the physical location of the heap, but the other ZDSHP displays for RSH requested areas say the area is in RSH even if some part of it is physically allocated in 64 bit system heap. Since 64 bit system heap will be lost across an IPL, if an RSH requested area was fulfilled in any part by 64 bit system heap it will be lost across an IPL. Knowing whether a large RSH area will be lost across an IPL could influence decisions made about whether or not to IPL if a problem occurs.

If there were a way to see whether any RSH requested area is backed by 64 bit system heap, it would be very easy to know if any RSH areas would be lost across an IPL which would help making decisions about the impact of an IPL during problems.

Idea priority Medium
  • Guest
    Apr 30, 2025
    The capability requested in this idea is already available.

    The SHEAPC (and tpf_sheapc) API is used to allocate recoverable system heap. SHEAPC ACTION=GET will obtain a system heap buffer. If the request was for a recoverable system heap buffer, the GET will obtain a buffer in either the recoverable system heap area or the 64-bit system heap area. It will not be split between the two areas.

    SHEAPC ACTION=EXTEND will obtain another system heap buffer that is associated with the unique token (ISHPXUT) that is required for the SHEAPC call. In order to use the EXTEND option, a GET using the same unique token must have been done first. It is possible that the system heap buffer that was obtained by the GET and by the EXTEND are in different areas. For example, the GET might have obtained a system heap buffer in the recoverable system heap area and the EXTEND might have obtained the buffer in the 64-bit area. This is the scenario that is being discussed in this idea.

    ZDSHP FIND buffer_address only locates the first system heap buffer that is associated with the unique token. Therefore, you can only see the system heap area for the first buffer.

    ZDSHP unique_token shows all associated buffers with the unique token. This includes the system heap area where they reside.

    The ZDSHP unique_token option provides what has been requested by this idea.
    Reply

By clicking the "Post Comment" or "Submit Idea" button, you are agreeing to the IBM Ideas Portal Terms of Use.
Do not place IBM confidential, company confidential, or personal information into any field.