I have a related question, maybe someone who is more familiar with
bpxwunix() knows - does it do a spawn() or a fork()/exec() under the
covers? If spawn(), is it possible to do a local spawn? The doc that I
see is silent.
I'm also not a REXX expert, but what about running your REXX ISPF dialog
with syscalls('ON') and then using the REXX syscalls directly?
Could you use the spawn()/spawnp() syscall with a "local spawn"? Then,
you will only be dubbing once (at syscalls('ON')), and you wouldn't be
starting a new OMVS address spaces.
I know that you can have an ISPF dialog program written in C/C++ that uses
the C library to do Unix stuff: the first thing that does a UNIX syscall
will dub the address space. You can use (local) spawn to invoke other
commands in child processes but in the same address space. We've done
this before and it works well.
On the other hand, maybe your performance problem is something specific to
your dev system, and otherwise not really significant? Try posting a tiny
REXX test case and maybe others on the list will see what kind of
performance they get.
Kirk Wolf
Dovetailed Technologies
http://dovetail.com
On Thu, Dec 12, 2019 at 6:07 AM Lionel B Dyck <[email protected]> wrote:
> Thanks for the update on STEPLIB - I didn't see it in 2.1 but my search
> may have been using the wrong keywords.
>
> I did some testing doing bpxwunix from rexx. 1 test was issuing the env
> command and the other a cd followed by an ls -la.
>
> With libraries in STEPLIB and in ISPLLIB the timing on my system (which is
> a z/VM guest) was 10 and 4 seconds respectively under ISPF and 4 and 2
> seconds in native TSO. This pointed to the ISPLLIB as a tasklib so I
> removed everything from it and the timing under ISPF went from 10 down to 7
> seconds and 4 to 1 seconds. Removing the STEPLIB got me to 2 and 0.5
> seconds.
>
> Still not subsecond so I suspect there is something in the z/VM setup
> which I'm not sure how to diagnose but am looking.
>
> Thanks
>
>
> Lionel B. Dyck <sdg><
> Website: http://www.lbdsoftware.com
>
> "Worry more about your character than your reputation. Character is what
> you are, reputation merely what others think you are." - John Wooden
>
> -----Original Message-----
> From: IBM Mainframe Discussion List <[email protected]> On Behalf
> Of Kirk Wolf
> Sent: Wednesday, December 11, 2019 7:20 PM
> To: [email protected]
> Subject: Re: OMVS Tuning ?
>
> Lionel,
>
> STEPLIB=none has been around for a long time, and I see it documented, for
> example, in the V1R13 z/OS UNIX Planning book.
>
> Can you offer any more details as to where the performance is bad or how
> you notice? I would assume that what you are describing is something
> relative to the time required to do a fork/exec or spawn. Which? local
> spawn?
>
> On Wed, Dec 11, 2019 at 2:04 PM Lionel B Dyck <[email protected]> wrote:
>
> > Found one major issue - the systems where the issue is are z/OS 2.1
> > and the STEPLIB=none variable looks to have been new in 2.2. Reducing
> > the STEPLIB and ISPLLIB solved things.
> >
> >
> > Lionel B. Dyck <sdg><
> > Website: http://www.lbdsoftware.com
> >
> > "Worry more about your character than your reputation. Character is
> > what you are, reputation merely what others think you are." - John
> > Wooden
> >
> > -----Original Message-----
> > From: IBM Mainframe Discussion List <[email protected]> On
> > Behalf Of Lionel B Dyck
> > Sent: Wednesday, December 11, 2019 12:58 PM
> > To: [email protected]
> > Subject: OMVS Tuning ?
> >
> > I am working on a project where the omvs performance on some systems
> > is slower than one would like -definitely not sub-second.
> >
> >
> >
> > I'm looking for tuning suggestions.
> >
> >
> >
> > When under ISPF the elapsed time is more than double the elapsed time
> > when in native TSO.
> >
> >
> >
> > Note that the OMVS environment includes STEPLIB=none but my guess is
> > that the ISPLLIB may be the culprit when under ISPF - I just can't
> > prove that (yet).
> >
> >
> >
> > Thanks for any guidance.
> >
> >
> >
> >
> >
> > Lionel B. Dyck <sdg><
> > Website: <http://www.lbdsoftware.com/> http://www.lbdsoftware.com
> >
> > "Worry more about your character than your reputation. Character is
> > what you are, reputation merely what others think you are." - John
> > Wooden
> >
> >
> >
> >
> > ----------------------------------------------------------------------
> > For IBM-MAIN subscribe / signoff / archive access instructions, send
> > email to [email protected] with the message: INFO IBM-MAIN
> >
> > ----------------------------------------------------------------------
> > For IBM-MAIN subscribe / signoff / archive access instructions, send
> > email to [email protected] with the message: INFO IBM-MAIN
> >
>
> ----------------------------------------------------------------------
> For IBM-MAIN subscribe / signoff / archive access instructions, send email
> to [email protected] with the message: INFO IBM-MAIN
>
> ----------------------------------------------------------------------
> For IBM-MAIN subscribe / signoff / archive access instructions,
> send email to [email protected] with the message: INFO IBM-MAIN
>
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN
