Patty,

We do essentially the same thing - although not nearly as often.  We
refresh our test LPAR every 6 months or so - always on a by-request
basis because we also have Oracle sitting on unix that is kept in sync
with the databases on the "Z" so it is a big to-do when we refresh.
When we refresh the test LPAR, I make sure it is done on a weekend and I
use DFDSS full volume using flashcopy=copy.

For our normal backups, we perform a database backup every night before
running our batch cycle, using DFDSS flashcopy=nocopy.  While the batch
cycle is running, we're spinning the flash volumes to tape.  Once the
batch cycle is done, we do DFDSS flashcopy=nocopy of the entire system
then spin the flash volumes off to tape after the operator has left for
the night.

I just checked RMF from last night and our DS6800 was performing just
fine while the early database spin to tape was running.  My busiest
database pack was pushing 300 I/Os per second thru it with 1 millisecond
response time (at a whopping 14% busy!)  The backups weren't showing as
impressive as numbers, but they were also moving large blocks of data.

We upgraded to the DS6800 about 15 months ago from an RVA.  Moving from
SNAPSHOT to FLASHCOPY was a bit of an adjustment, but we're real happy
with the performance of the DS6800 - including the flashcopy.  Not to
mention seeing the UPS usage drop drastically when we unplugged the old
RVA.

Rex

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On
Behalf Of Patty Mabie
Sent: Thursday, September 27, 2007 2:12 PM
To: [email protected]
Subject: Flashcopy on DS6800

We installed a DS6800 to replace our Shark F20 a few weeks ago.  We are
happy with the change overall and have seen good improvements in batch
times.  However, we do have an issue with the Flashcopy.  

On the F20 we did a nightly FDRABR flashcopy with parameter FCOPY=COPY
of  about 64 3390-9 and about 15 3390-3 volumes. Our tapes are old and
slow, and it was time consuming to back this all up for DR, so we did a
second flash copy using DFDSS that would invoke flash copy services.
Those volumes would remain offline, only being used for backups. We we
then did FDRBACKUP 
of the flashed volumes, and brought them online for our TESTLPAR.   
 
We now do a similar process on the DS6800.
 
We do 2 flashes, 1 using FDRFLASH with FCOPY=COPY to make full copies to
be used by our TESTLPAR. The second is FDRABR with the FCOPY=COPY and
these are used for our FDR disaster backups. 
 
The # of drives that are being copied with FCOPY=COPY are equal or less
on 
the DS6800.  We saw no performance hit when doing this on the SHARK F20.

We are having terrible response on the DS6800 for about 2 hours after
the flashcopy completes.  

After reviewing with IBM, we made a few adjustments when we learned
about half the volumes were being copied to targets in the same extent
pool as the source.  We switched our target volumes to extent pools
different from the source volumes, and also validated that the target
and source for each flashed volume are managed by the same controller.
This seemed to have little effect.
 
What are considering switching to this process:  Do 2 flash copies, 1
with FDRFLASH with FCOPY=NOCOPY and a second with FDRABR with
FCOPY=NOCOPY. We will then bring the first copy online to the test LPAR
and the second will be used just for FDR disaster backups. The first
copy will be repeated once a week (or on demnad), all other days during
the week we will do just the FDRABR copy for disaster purposes.
 

We are wondering if the same process works differently on the Shark v.
the 6800.  Does anyone else use flashcopy for TESTLPAR data?  If so, are
you using FULLCOPY, NOCOPY or incremental flashing.  Any comments on the
process we are using or the one we propose to change to?  Is there any
issue in maintaining a flash pair for a week or to without using
FCOPY=COPY ?

Would appreciate any comments.

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