Kris,
Thanks. That's interesting reading. The system in question does not
have DB2/VM, and the 3 SFS filepools have no directories eligible for
dataspaces. Any other ideas? Do NOMAD2 Shared Databases use
dataspaces? I know this system has NOMAD2 Shared Databases, but as
we're just getting familiar with it, I don't know their userids. I
don't think there's anything wrong with the system, it's just curiosity,
so it's not worth any great effort.
Dennis O'Brien
"Elected office holds more perks than Elvis' nightstand." -- Dennis
Miller
-----Original Message-----
From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On
Behalf Of Kris Buelens
Sent: Saturday, May 17, 2008 11:52
To: [email protected]
Subject: Re: [IBMVM] Mystery paging
Are dataspaces being used? DB2 and SFS are the the most common
examples. With dataspaces (mapped to minidisks), the application
simply reference the storage, CP will page-in what is referenced, and
that is counted as paging.
CP's Q SPACES and IND SPACE commands can help you.
On VM's web-site, there is a document were I describe this in more
detail:
http://www.vm.ibm.com/perf/tips/dim.html
http://www.vm.ibm.com/perf/tips/vmdspage.html
2008/5/17 O'Brien, Dennis L <Dennis.L.O'[EMAIL PROTECTED]>:
>
> We recently inherited responsibility for a z/VM 5.2 system that had
been
> maintained by another group. They had a DR test today, and I logged
on
> and looked around. The LPAR is configured with 3G central storage and
> no expanded storage. I issued the following commands:
>
> q alloc page
> EXTENT EXTENT TOTAL PAGES HIGH %
> VOLID RDEV START END PAGES IN USE PAGE USED
> ------ ---- ---------- ---------- ------ ------ ------ ----
> VMPG00 8719 1 1000 180000 1 1 1%
> VMPG01 871A 1 1000 180000 0 0 0%
> VMPG02 871B 1 1000 180000 0 0 0%
> VMPG03 871C 1 1000 180000 0 0 0%
> ------ ------ ----
> SUMMARY 720000 1 1%
> USABLE 720000 1 1%
> Ready;
> ind
> AVGPROC-003% 01
> MDC READS-000112/SEC WRITES-000003/SEC HIT RATIO-093%
> PAGING-13/SEC STEAL-000%
> Q0-00003(00000) DORMANT-00141
> Q1-00000(00000) E1-00000(00000)
> Q2-00001(00000) EXPAN-001 E2-00000(00000)
> Q3-00000(00000) EXPAN-001 E3-00000(00000)
>
> PROC 0000-003%
>
> LIMITED-00000
> Ready;
> q xstor
> Expanded storage is not available within this hardware configuration.
> Ready(01401);
>
> Since there's no expanded storage, where are those 13 pages/second
> going? Is the system reading the one page that's out on DASD 13 times
a
> second? I did another Q ALLOC PAGE after the IND, and there's still
> only one page out there.
>
> Dennis O'Brien
>
> "Elected office holds more perks than Elvis' nightstand." -- Dennis
> Miller
--
Kris Buelens,
IBM Belgium, VM customer support
