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Thanks to Dale & P. Saint Jacques,
One other question:
For DMS - as we have scope to re-configure the SSA;
with Raid 5 is it generally better to have more containers for parallelism
with fewer disks per logical drive (3 disks +1 for parity on raid 5) versus
fewer containers with more disks per logical drive (5 +1) ?
i.e. which is likely to give better performance on
500-700 gb database with 36gb SSA disks raid
5
a) 8 containers with 4
disks per container (3+1parity) = 1152 gb
or
b) 4 containers with 6 disks per
container (5+1parity) = 864 gb
Please ignore the storage overhead, which would
perform better ? (I prefer a))
Thanks
Dave Bargeron
LloydsTSB Bank
United Kingdom
----- Original Message -----
Sent: Wednesday, May 30, 2001 9:29
PM
Subject: Re: DB2EUG: UDB Downsize
You can resize the containers to a minimum size you chose for
SMS containers.
For DMS containers V7 still limits you the high water mark
attained for each container of your current db.
The situation occurs
because in the backup image the files that are your tablespace descriptors:
SQLSPCS.1 and SQLSPCS.2 contain info on the high water mark of each container.
As you restore, these are brought back with the image and your redirect
definitions will be compared to those high water mark values.
So do a LIST TABLESPACE CONRAINERS FOR x SHOW DETAIL where x is the tblsp.
id to find the high water marks of each container to redirect.
Apart from that, what you are planning to do should work.
David Bargeron wrote:
Dear List, I need to resize
downwards.... We (&
the business !) over-estimated the sizing of a database (UDB 7.1 on NT 4.0);
instead of being around 1 terabyte it will come to around 500gb, we would
like to free up the extra 500gb SSA for other uses. Our plan is to backup the existing database, resize
the containers accordingly smaller with fewer disks per array and then do a
redirected restore into the new
containers. (The largest containers are for LOB data 6 disks per array + 1
for parity.) Any comments
would be greatly appreciated. Thanks Dave
BargeronLloydsTSB
BankUnited
Kingdom
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