Here is the full trace. I'll gladly accept any help in interpreting.
Sorry about the bad formatting.
SYS5 SGTDEM64 00000063 12:44:53.270019 Demote 1M 64 bit page
FUNC1... COPYSRVH High Virtual Copy Service
JOBN1... ZUMCCMG1 ASID1... 0215 PLOCKS.. 8800C001 CPU..... 0006
JOBN2... ZUMCCMG3 ASID2... 022D RLOCKS.. 8800C001 RLOCKDET 0800
ADASID.. 0215 XMASID.. 022D CMASID.. 0000 STASID.. 0000
KEY..... 0036 ADDR.... 035E1008 ALET.... 00000000
70207520 C710
KEY..... 009A ADDR.... 035E22B0 ALET.... 00000000
035E22F8 00000000 00000000 00000000 00000000 00000000 01000000 00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000
KEY..... 009B ADDR.... 035E22F8 ALET.... 00000000
00000001 01000003 7FF74D38 04134B00 0000003B E5398D00 00000000 00000000
00000000 00000000 00000050 1A000000 00000000 00000000 00000000 00000000 00000000
00000000
Robert Crawford
Mainframe Management
United Services Automobile Association
(210) 913-3822
« Des clochards comme nous, bébé nous sommes nés pour courir » - Voltaire
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-----Original Message-----
From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Jim
Mulder
Sent: Wednesday, June 2, 2021 11:21 AM
To: [email protected]
Subject: EXTERNAL: Re: Why Would COPYSRVH Cause a 1M Page Demtion [Internal]
Please show the entire trace entry.
Jim Mulder z/OS Diagnosis, Design, Development, Test IBM Corp.
Poughkeepsie NY
"IBM Mainframe Discussion List" <[email protected]> wrote on
06/01/2021 04:12:18 PM:
> From: "Crawford, Robert C."
<[email protected]>
> To: [email protected]
> Date: 06/02/2021 12:06 PM
> Subject: Why Would COPYSRVH Cause a 1M Page Demtion [Internal] Sent
> by: "IBM Mainframe Discussion List" <[email protected]>
>
> I've been trying to track down what's causing system 1M page demotions
> on our test system. The component trace IBM gave me shows, in
part:
>
> SYS5 SGTDEM64 00000063 12:44:53.270019 Demote 1M 64 bit page
> FUNC1... COPYSRVH High Virtual Copy Service
> JOBN1... ZUMCCMG1 ASID1... 0215 PLOCKS.. 8800C001 CPU..... 0006
> JOBN2... ZUMCCMG3 ASID2... 022D RLOCKS.. 8800C001 RLOCKDET 0800
> KEY..... 0036 ADDR.... 035E1008 ALET.... 00000000
>
> The COPYSRVH function isn't well documented but, from I see, UNIX fork
> processing invokes it to copy memory to the new process. This makes
> sense in that JOBN1 and JOBN3 are both USS processes.
>
> Both LFAREA and SCM on this system are less than 1% used. Why is z/
> OS demoting pages?
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