ZVM 5.2, Z890, and I/O

[David Kreuter]

without any other workload analysis: 6g central 2g xstore.
on a z/9 we have not experienced or noticed >2g i/o issues.

David


-----Original Message-----
From: VM/ESA and z/VM Discussions on behalf of Hughes, Jim - OIT
Sent: Mon 3/6/2006 4:23 PM
To: VMESA-***@LISTSERV.UARK.EDU
Subject: ZVM 5.2, Z890, and I/O

Is there a problem with ZVM 5.2 and a Z890 when doing I/O over the 2 gig
line?

We are probably getting a Z890 with 8 gig of main storage. Any
suggestions for carving up the main storage(xstore, cache, etc.)

_______________________
Jim Hughes
603-271-5586
"Impossible is just an opinion."

[Tom Duerbusch]

First, you don't have 8 GB. You will loose at least 768 MB for
microcode etc.

Second, how many LPARs?

Third, in each LPAR, you need to determine what operating system you
will run.

Fourth, if you are running VM, how much central and how much xstore you
need.

Fifth, bug management on buying another 8 GB (rumor has it that
storage is running about half price now a days). The Z8, replacement
for the Z890, may have 16 GB increments. (Is it April yet?)

Tom Duerbusch
THD Consulting


>>> ***@oit.nh.gov 3/6/2006 3:23 PM >>>
Is there a problem with ZVM 5.2 and a Z890 when doing I/O over the 2
gig
line?

We are probably getting a Z890 with 8 gig of main storage. Any
suggestions for carving up the main storage(xstore, cache, etc.)

_______________________
Jim Hughes
603-271-5586
"Impossible is just an opinion."

[Jim Elliott]

> Is there a problem with ZVM 5.2 and a Z890 when doing I/O over
> the 2 gig line?

With z/VM V5.2 there is effectively no 2GB line issue.

> We are probably getting a Z890 with 8 gig of main storage. Any
> suggestions for carving up the main storage(xstore, cache,
> etc.)

Once you take away the HSA (somewhere between 768M and 1GB!), split
it up 25% xstore, 75% cstore. "Your mileage may vary."

Jim