Sorry, but 360 timings have no relevance to today's systems.  Out-of-order 
processing, executing up to 6 instructions concurrently and a myriad of other 
factors make accurate timings impossible.

Cache utilization is one of the biggest factors. Processing more data than the 
L1 and L2 caches can hold will really mess things up.  Most people don't have 
to worry about that, unless you have large tables in memory that you access a 
lot, especially randomly.

Chris Blaicher
Technical Architect
Syncsort, Inc.


-----Original Message-----
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf 
Of Giliad Wilf
Sent: Tuesday, August 13, 2019 10:29 AM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: Instruction speeds

On Mon, 12 Aug 2019 20:48:18 -0400, Brian Chapman <bchapma...@gmail.com> wrote:

>Hi everyone,
>
>I did some searching, but I didn't find anything that really discussed 
>this on the topic that I'm interested. Is there anything published that 
>compares the cycle times of the most used instructions?
>
>For example; moving an address between areas of storage. I would assume 
>that executing a LOAD and STORE would be much quicker than executing a MVC.
>
>Or executing a LOAD ADDRESS to increment a register instead of ADD HALF 
>WORD.
>
>Or does this really matter as much as ordering the instructions so they 
>are optimized for the pipeline?
>

There used to be, with every new IBM System/360 machine, a "Functional 
Characteristics" publication stating "Instruction Times" in microseconds.
Here is one for the IBM System/360 Model 85:

http://www.bitsavers.org/pdf/ibm/360/funcChar/A22-6916-1_360-85_funcChar_Jun68.pdf

See page 27.

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