Re: 5 instances = too much ???

I have currently got 30 instances RUNNING (some others closed down) on my HP K420 server.
I have 2 Gb main memory and quite a lot of disc space ! It's a major pain in maintenance and I am slowly getting through an exercise of merging instances to reduce the overheads involved.

Now, most of these are running in NOARCHIVELOG mode - they are 'don't care' instances, used by our various teams of developers to test small, medium and large volumes of data. They are not tuned to perfecting and if I found the setupo I have got here on a customer site, I would be rather upset. With this many instances it is difficult to spread datafiles etc over a number of discs/controllers because you only have a limited amount of each.

The reason we have so many, is probably down to bad (ish) application design where the designers have partitioned over 5 partitions and hard coded the tablespace names - which means that they only need to maintain one set of maintenance scripts for upgrades etc. Unfortunately, it means that some user accounts interfere with others when running batch or OLTP processing.

So, I would say that there are reasons for having numerous instances, and reasons for not having all that many - but it depends on how your company is/was/intends to run and how it was set up in the past. I inherited most of what I have now and have contributed to it as well :o(.

Good luck.

Norman.

Norman Dunbar		EMail:	NDunbar_at_LynxFinancialSystems.co.uk
Database/Unix administrator	Phone:	0113 289 6265
Lynx Financial Systems Ltd.	Fax:	0113 201 7265
			URL:	http://www.LynxFinancialSystems.com


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