Discussion:
Question about VSMLIST and LSQA
Add Reply
Joe Reichman
2017-07-30 01:57:16 UTC
Reply
Permalink
Raw Message
Hi



Since LSQA is System Private Storage how come there isn't a TCB associated
with it



thanks


----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Binyamin Dissen
2017-07-30 06:51:38 UTC
Reply
Permalink
Raw Message
On Sat, 29 Jul 2017 21:48:24 -0400 Joe Reichman <***@GMAIL.COM> wrote:

:>Since LSQA is System Private Storage how come there isn't a TCB associated
:>with it

Who said there isn't?

--
Binyamin Dissen <***@dissensoftware.com>
http://www.dissensoftware.com

Director, Dissen Software, Bar & Grill - Israel


Should you use the mailblocks package and expect a response from me,
you should preauthorize the dissensoftware.com domain.

I very rarely bother responding to challenge/response systems,
especially those from irresponsible companies.

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Joe Reichman
2017-07-30 13:36:45 UTC
Reply
Permalink
Raw Message
Sorry Binyamin

Didn't see your reply the VSM Descriptor when looking for LSQA allocated has
zeros for the TCB field

thanks

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-***@LISTSERV.UA.EDU] On
Behalf Of Binyamin Dissen
Sent: Sunday, July 30, 2017 2:53 AM
To: IBM-***@LISTSERV.UA.EDU
Subject: Re: Question about VSMLIST and LSQA

On Sat, 29 Jul 2017 21:48:24 -0400 Joe Reichman <***@GMAIL.COM>
wrote:

:>Since LSQA is System Private Storage how come there isn't a TCB associated
:>with it

Who said there isn't?

--
Binyamin Dissen <***@dissensoftware.com> http://www.dissensoftware.com

Director, Dissen Software, Bar & Grill - Israel


Should you use the mailblocks package and expect a response from me, you
should preauthorize the dissensoftware.com domain.

I very rarely bother responding to challenge/response systems, especially
those from irresponsible companies.

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions, send email
to ***@listserv.ua.edu with the message: INFO IBM-MAIN

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Binyamin Dissen
2017-07-30 16:51:44 UTC
Reply
Permalink
Raw Message
It appears that VSMLIST is documented as not returning the TCB address for
LSQA subpools because it treats all LSQA as address space level LSQA.

One can wonder why, but it is documented.


On Sun, 30 Jul 2017 09:37:53 -0400 Joe Reichman <***@GMAIL.COM> wrote:

:>Sorry Binyamin
:>
:>Didn't see your reply the VSM Descriptor when looking for LSQA allocated has
:>zeros for the TCB field
:>
:>thanks
:>
:>-----Original Message-----
:>From: IBM Mainframe Discussion List [mailto:IBM-***@LISTSERV.UA.EDU] On
:>Behalf Of Binyamin Dissen
:>Sent: Sunday, July 30, 2017 2:53 AM
:>To: IBM-***@LISTSERV.UA.EDU
:>Subject: Re: Question about VSMLIST and LSQA
:>
:>On Sat, 29 Jul 2017 21:48:24 -0400 Joe Reichman <***@GMAIL.COM>
:>wrote:
:>
:>:>Since LSQA is System Private Storage how come there isn't a TCB associated
:>:>with it
:>
:>Who said there isn't?

--
Binyamin Dissen <***@dissensoftware.com>
http://www.dissensoftware.com

Director, Dissen Software, Bar & Grill - Israel


Should you use the mailblocks package and expect a response from me,
you should preauthorize the dissensoftware.com domain.

I very rarely bother responding to challenge/response systems,
especially those from irresponsible companies.

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Jim Mulder
2017-07-31 06:59:25 UTC
Reply
Permalink
Raw Message
LSQA storage is internally represented by data structures that are very

different from the non-LSQA private area data structures. The LSQA data
structures are not task related. For example, subpools 253, 254, and 255
are internally the same subpool, and a single 4K page (and thus a single
VSMLIST allocated storage descriptor) can contain storage for all 3 of
these subpools. The VSMLIST allocated storage descriptor always
says subpool 255, even though it may represent storage obtained
via a combination of subpool 253, 254, and 255 requests.

For purposes of freeing task or jobstep task owned LSQA, each TCB
points to chains of AEs (IHAAE). AEs are not processed by VSMLIST.-

Jim Mulder z/OS Diagnosis, Design, Development, Test IBM Corp.
Poughkeepsie NY
Date: 07/31/2017 02:29 AM
Subject: Re: Question about VSMLIST and LSQA
It appears that VSMLIST is documented as not returning the TCB address for
LSQA subpools because it treats all LSQA as address space level LSQA.
One can wonder why, but it is documented.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Peter Relson
2017-07-31 14:51:10 UTC
Reply
Permalink
Raw Message
Post by Binyamin Dissen
Post by Joe Reichman
Since LSQA is System Private Storage how come there isn't a TCB
associated
Post by Binyamin Dissen
Post by Joe Reichman
with it
Who said there isn't?
VSM said so.

LSQA, as shown in the subpool table in the books, has a variant that is
associated with the current task, one that is associated with the jobstep
task, and one that is not associated with any task (for example, see
subpools 253, 254, 255).

A key reason for the last is so that someone can use LSQA for an SRB that
is not associated with a TCB, for which you might not want private storage
obtained by the SRB to be freed just because some task terminates.

I do not know whether the task association for subpools 253 and 254 is
surfaced by VSMLIST.

Peter Relson
z/OS Core Technology Design


----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Binyamin Dissen
2017-08-01 17:49:15 UTC
Reply
Permalink
Raw Message
On Mon, 31 Jul 2017 10:52:15 -0400 Peter Relson <***@US.IBM.COM> wrote:

:>>>Since LSQA is System Private Storage how come there isn't a TCB
:>associated
:>>>with it

:>>Who said there isn't?

:>VSM said so.

Because VSMLIST is not examining the correct control blocks, As Jim Mulder
stated, " AEs are not processed by VSMLIST.- ".

:>LSQA, as shown in the subpool table in the books, has a variant that is
:>associated with the current task, one that is associated with the jobstep
:>task, and one that is not associated with any task (for example, see
:>subpools 253, 254, 255).

:>A key reason for the last is so that someone can use LSQA for an SRB that
:>is not associated with a TCB, for which you might not want private storage
:>obtained by the SRB to be freed just because some task terminates.

Seems like a weak reason. Are there other ways SRBs are protected from poor
subpool choices?

:>I do not know whether the task association for subpools 253 and 254 is
:>surfaced by VSMLIST.

As Jim Mulder stated, no.

--
Binyamin Dissen <***@dissensoftware.com>
http://www.dissensoftware.com

Director, Dissen Software, Bar & Grill - Israel


Should you use the mailblocks package and expect a response from me,
you should preauthorize the dissensoftware.com domain.

I very rarely bother responding to challenge/response systems,
especially those from irresponsible companies.

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Peter Relson
2017-08-02 12:35:44 UTC
Reply
Permalink
Raw Message
Post by Binyamin Dissen
Post by Peter Relson
A key reason for the last is so that someone can use LSQA for an SRB
that
Post by Binyamin Dissen
Post by Peter Relson
is not associated with a TCB, for which you might not want private
storage
Post by Binyamin Dissen
Post by Peter Relson
obtained by the SRB to be freed just because some task terminates.
Seems like a weak reason. Are there other ways SRBs are protected from
poor
Post by Binyamin Dissen
subpool choices?
It is far from a weak reason. It is an extremely strong reason.
If this is a "poor subpool choice" then what would be a good subpool
choice?

Any task-related subpool will have its storage freed when that task
terminates. An SRB *can* (but need not) be tied to a particular task. When
it is, it can rely on a task-owned subpool associated with that task (or a
parent of that task). When it is not, it ought not to rely on such.

The SRB, in that case, needs to use a subpool that has no task
association. That is either LSQA or common. If anything, I'd say that
common would be a "poor subpool choice" if addressability from multiple
address spaces is not needed.

Peter Relson
z/OS Core Technology Design


----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Steve Smith
2017-08-02 15:31:25 UTC
Reply
Permalink
Raw Message
In sorting through the Rubik's Cube that is the subpool selection charts,
it appears to me that 233-235 are defined exactly the same as 253-255
respectively. Is there some difference I'm missing?

sas

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Don Poitras
2017-08-02 16:48:04 UTC
Reply
Permalink
Raw Message
Post by Steve Smith
In sorting through the Rubik's Cube that is the subpool selection charts,
it appears to me that 233-235 are defined exactly the same as 253-255
respectively. Is there some difference I'm missing?
sas
If there was a difference, that would be a problem. Since the note for
all three subpools says they are actually allocated in the corresponding
subpool. I would guess that there was some historic difference, but not
any more.
--
Don Poitras - SAS Development - SAS Institute Inc. - SAS Campus Drive
***@sas.com (919) 531-5637 Cary, NC 27513

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Steve Smith
2017-08-02 19:25:36 UTC
Reply
Permalink
Raw Message
I asked the question based on the Auth. Ass. Services Guide... later on, I
looked at the Diagnosis Ref., which says that the 230s are allocated in the
250s. Ah well, it was only idle curiosity anyway.
In article <CA+AiZz3LU-+-mJ9ROp7iesLCSDbzr1qdmjJ3e-
Post by Steve Smith
In sorting through the Rubik's Cube that is the subpool selection charts,
it appears to me that 233-235 are defined exactly the same as 253-255
respectively. Is there some difference I'm missing?
sas
If there was a difference, that would be a problem. Since the note for
all three subpools says they are actually allocated in the corresponding
subpool. I would guess that there was some historic difference, but not
any more.
--
Don Poitras - SAS Development - SAS Institute Inc. - SAS Campus Drive
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
--
sas

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Don Poitras
2017-08-02 21:03:01 UTC
Reply
Permalink
Raw Message
The convention for the past 15 years or so has been first two letters of
first name and first four letters of last name. So you'd probably be
***@sas.com. For collisions, I think it goes to three and three, so
possibly ***@sas.com. You could always try to bribe somebody to be
***@sas.com though. Reminds me of the Heinlein book where there was
a character known as "Rudbeck of Rudbeck at Rudbeck". :)
Post by Steve Smith
I asked the question based on the Auth. Ass. Services Guide... later on, I
looked at the Diagnosis Ref., which says that the 230s are allocated in the
250s. Ah well, it was only idle curiosity anyway.
In article <CA+AiZz3LU-+-mJ9ROp7iesLCSDbzr1qdmjJ3e-
Post by Steve Smith
In sorting through the Rubik's Cube that is the subpool selection charts,
it appears to me that 233-235 are defined exactly the same as 253-255
respectively. Is there some difference I'm missing?
sas
If there was a difference, that would be a problem. Since the note for
all three subpools says they are actually allocated in the corresponding
subpool. I would guess that there was some historic difference, but not
any more.
--
Don Poitras - SAS Development - SAS Institute Inc. - SAS Campus Drive
***@sas.com (919) 531-5637 Cary, NC 27513

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to ***@listserv.ua.edu with the message: INFO IBM-MAIN
Loading...