The answer is maybe ("maybe" being a good analog of the performance
mavens' "it depends"). It was such a short period that it will be
difficult to make the determination, especially this far after the fact.
It is likely that users were logging off at about that time;
logoff/logon is used as a quick way to clean up a machine by many of the
guests.
Regards,
Richard Schuh
> -----Original Message-----
> From: The IBM z/VM Operating System
> [mailto:[email protected]] On Behalf Of Bill Holder
> Sent: Monday, January 05, 2009 1:27 PM
> To: [email protected]
> Subject: Re: VDISK
>
> On Tue, 23 Dec 2008 14:39:43 -0800, Schuh, Richard
> <[email protected]> wrot=
> e:
>
> >In looking at the VDISK Storage by User display (ESALPS) I
> noticed that
> >SYSTEM was the 10th largest user of VDISK during one
> interval, but fell
> >to 0 the next. What causes SYSTEM to show up as a user of VDISK?
> >Perhaps=
>
> >something in the DEFINE or DETACH processes?
> >
> >Regards,
> >Richard Schuh
> >
> >
> >
>
> I suspect this is an artifact of the vdisk design - the virtual
> storage behind vdisks is implemented as shared system-owned spaces.
> When a vdisk goes away, the vdisk address space can momentarily go
> through an oddball transient "system private" state, which may have
> been captured in that interval. Were vdisks being detached or
> vdisk users logging off right about then?
>
> - Bill Holder, z/VM Development, IBM
>
