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How can I reduce CPU usage in REXX program.

 
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Mansik Kim

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Joined: 15 Dec 2006
Posts: 29
Location: Korea

PostPosted: Mon Sep 03, 2012 8:01 pm    Post subject: How can I reduce CPU usage in REXX program.
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Hello,

I working REXX program read and calculation multi line(about 10million line).

This job used 30 min cpu time and 50 min elapsed time and
about 20% cpu used during job running.

I want to have solution for reduce cpu and elapsed time.

Please let me have.

Thanks,
Mansik.
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Anuj Dhawan

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Joined: 22 Apr 2006
Posts: 6258
Location: Mumbai, India

PostPosted: Mon Sep 03, 2012 8:08 pm    Post subject:
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Possibly, start by showing code snippet. Bit off topic but a "10million" is number of records the REXX work on or the number-of-code-lines in REXX? If it's later, possibly, just post the "calcualtion-part" from your REXX-code (and a TRACE)...
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enrico-sorichetti

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Joined: 14 Mar 2007
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Location: italy

PostPosted: Mon Sep 03, 2012 8:22 pm    Post subject: Reply to: How can I reduce CPU usage in REXX program.
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Quote:
And "10million" is number of records in input or the number-of-code-lines in REXX?
icon_eek.gif icon_eek.gif icon_eek.gif

just run a small experiment, without carrying on any computation
just read the 10 millions record...
and You will see that the most of the time is spent doing the I/O

You will see that what You ask cannot be done, REXX i/o is just a resource hog.

not to talk about stemmed variables.
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Anuj Dhawan

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Joined: 22 Apr 2006
Posts: 6258
Location: Mumbai, India

PostPosted: Mon Sep 03, 2012 8:35 pm    Post subject:
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Thanks Enrico. Knowing REXX is not a good choice for "huge input", I was beaten up by
Quote:
I working REXX program read and calculation multi line(about 10million line).
and was fearful once I asked "Possibly, start by showing code snippet" and edited it later to add more confusion... icon_redface.gif. Just wanted to avoid some one posting a huge code... icon_rolleyes.gif.

Sorry for taking the discussion out of the context... icon_redface.gif
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enrico-sorichetti

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PostPosted: Mon Sep 03, 2012 8:37 pm    Post subject: Reply to: How can I reduce CPU usage in REXX program.
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icon_redface.gif my bad I had forgot the icon_wink.gif smiley icon_biggrin.gif
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dick scherrer

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Joined: 23 Nov 2006
Posts: 19270
Location: Inside the Matrix

PostPosted: Tue Sep 04, 2012 7:49 am    Post subject:
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Hello,

The TS may have dissappeared . . .

Quote:
How can I reduce CPU usage in REXX program.
Re-write in a language better suited for high volume data and calculations . . .
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enrico-sorichetti

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Location: italy

PostPosted: Tue Sep 04, 2012 1:35 pm    Post subject: Reply to: How can I reduce CPU usage in REXX program.
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the TS has this habit, I checked his other topics!
I deleted a few of them,where the TS asked, more info was requested, nothing was provided
( that' s why the <proof> is not there )

probably time to warn.
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Marso

REXX Moderator


Joined: 13 Mar 2006
Posts: 1218
Location: Israel

PostPosted: Tue Sep 04, 2012 8:38 pm    Post subject:
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Anuj Dhawan wrote:
"10million" is number of records the REXX work on or the number-of-code-lines in REXX?

I think icon_eek.gif icon_eek.gif icon_eek.gif is the appropriate emotion! icon_wink.gif
My monster REXX program (10 panels, 9 sql cursors, 4 ispf tables) has around 1500 lines of code (i.e. comments and empty lines excluded).
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Nic Clouston

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PostPosted: Tue Sep 04, 2012 11:13 pm    Post subject:
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10,000,000 lines of input processed in 50 minutes by Rexx - that is pretty good going.
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abhisingh

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Joined: 26 Apr 2012
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Location: India

PostPosted: Tue Oct 23, 2012 6:25 pm    Post subject: Reply to: How can I reduce CPU usage in REXX program.
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With my limited knowledge.. icon_rolleyes.gif

REXX is doing well what it is suppose to do..

Your code is of huge line count with various i/o that's why there is some performance issue. Better go for other powerful language for ur task.
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Ed Goodman

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Joined: 08 Jun 2011
Posts: 556
Location: USA

PostPosted: Wed Oct 24, 2012 10:42 pm    Post subject:
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This REXX needs to be in a museum of sorts. It should be in the Hall of Bad Decisions that Made Sense at the Time.

My guess is that someone had a need, realized they could cobble a good REXX in a few hours, tested it with a few dozen lines of input. That saved them the hours of paperwork and meetings needed to get a real program integrated into the system.

Now, the REXX has consumed FAR more time and money than the real program PLUS the time and money needed to have gotten it implemented.

So to all the paperwork wonks out there: Take notice!
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