We do have a performance monitor, but that was not the question. Rather, the 
question was, "What can be happening that would cause an increase in VMDTTIME 
for this machine?"

In the case cited below, I had complete control of the CMS machine in question 
and it was outwardly idle. Nothing was running under the covers except CMS. No 
reader files were arriving, no messages, etc. I will try it again after 
insuring that there is no SFS directory that is accessed. 

Regards,
Richard Schuh

 -----Original Message-----
From:   VM/ESA and z/VM Discussions [mailto:[EMAIL PROTECTED]  On Behalf Of 
Brian Nielsen
Sent:   Thursday, January 26, 2006 7:25 AM
To:     [email protected]
Subject:        Re: Charging Time

Tracking how many pages are resident for the userid over time would help 
answer your question.  If you don't have a performance monitor to give you 
that info, another userid issue periodic IND USER commands.

Putting the userid in question into a disabled wait and/or CP READ would 
eliminate code executing inside the virtual machine as a possible source.  
If you wanted a different way to get a warm-fuzzy that it wasn't CMS 
related processing, you could IPL a non-CMS system, like the standalone 
loader.

Brian Nielsen

On Wed, 25 Jan 2006 13:08:21 -0800, Schuh, Richard <[EMAIL PROTECTED]> wrote:

>Is the time spent stealing pages charged to the user whose pages are 
being stolen? If not, what else can add to the TTIME of an otherwise idle 
user?
>
>Let me set the stage. We are being required to FORCE DISCONNECT any user 
who has been idle more than x minutes (x still being debated). Trying to 
test the routine that does this, I logged on a general user and let it sit 
idle after falling through its PROFILE. It remained connected, so I could 
see that there were no messages being received that might be counted as 
TTIME. This user stayed connected for nearly an hour longer than the 
specified limit. In reviewing statistics gathered using ESAMON, there were 
several times during the period when the reported VMDTTIME was 
incremented, which in turn, caused the idle clock to be restarted. After 
several resets of the idle value, the user finally timed out and was 
disconnected. When ESAMON reports TTIME to the macro being used, it 
converts VMDTTIME to a decimal number rounded to 10000ths of a second, so 
these periodic increments were stepping in 10ths of milliseconds, not 
insignificant values for a z990. 
>
>This happened fairly early in the morning. We do not observe anything 
like it when we reach our normal daytime load. That is what made me think 
that it may be page steals. The rationale is that the pages are stolen 
more quickly when the machine is loaded, so they are all stolen very early 
in the idle period, not causing a noticeable lengthening of it. With a 
light load, there is much less a reason to steal pages; therefore it takes 
a much longer period to steal all of the idle user's pages and they are 
stolen in small clumps at random times, accounting for the unevenness of 
the incrementing of TTIME.  
>
>
>Regards,
>Richard Schuh
>========================================================================

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