Help with AI Extents

microedgenh

New Member
Hello. Our software is created with Progress and currently we are rolling out Progress 10.1B. In the past, we have not used AI extents but after taking the DBA class, I have restructured our database so that we are doing many new things, including using AI. I had it turned on when I loaded .d's and they filled up so my first question is...

1. Should I only enable AI once the .d's are loaded?

I am still a little hazy on their purpose and how they work and since the databases are on the customer sites and we have over 400 customers, I need this to work pretty seamlessly. That brings me to my next questions:

2. Should the 3 AI extents be fixed or should the last one be variable?
3. How often do they fill up?
4. Is there a way to automate the emptying of the AI extents so our customers (who are not computer savvy) won't even know this process is occuring?

Thank you for the help. Ann.
 
1) You should not enable ai until after your data is loaded. There are a number of maintenance tasks where you ought to consider disabling after-imaging -- dump & load, index rebuild, big data updates or purges... stuff like that. Of course you need to be extra sure of your backups any time you do such things.

2) Personally I find variable ai extents to be a whole lot easier to work with than fixed length extents. They don't fill up to a fixed point -- you empty them and archive them on a schedule. Every ai extent can be variable.

3) I also prefer to have 8 to 12 extents available. It lets me tinker with the process more easily. 3 is not enough -- it is just too easy to get in a stall situation with only 3 extents.

4) You just took the dba class and you're still confused? That's not good. I don't know where the break-down was but after-imaging really ought to be one of the primary focuses of such a course. If you learn nothing else you should have learned about after-imaging! Whether that's your fault or due to poor training I don't know but something went seriously wrong there.

5) You're on 10.1B. The new automatic ai archiver might be of interest and should have been covered in your training. On the other handing scripting it isn't very hard and can be more flexible. It all depends on your environment and your needs.

6) Not to be a smart-alec or anything but... if this needs to be deployed to 400 sites (and ai definitely needs to be deployed to all customers who have data that has value) then it really shouldn't be done by someone who is as vague on the concepts as you appear to be. Your company should either get you better trained or hire a consultant to help implement this.
 
Gee, thanks Tom, especially for the "vague" comment. Our customers already have progress and our software...this is an upgrade. There has never been a DBA position here before and the programmers never used AI extents. I didn't even know about them until the class so I am bringing us up to date with the way things should be done. Thanks for your help.
 
Sorry, I'm not trying to be offensive. I probably should have repeated your use of the term "hazy".

I'm sympathetic to your plight and trying to be clear. Which probably seems rude. IMHO the concepts behind after-imaging should not be "hazy" after a DBA training class. If they are hazy (or vague) then something has gone wrong.

Deploying after-imaging to 400 clients (after the fact) is non-trivial and I don't think that it is something that I would want a hazy DBA doing. It is very important to get done and done right. You should get un-hazy ASAP. Asking questions is a good start.

Hopefully you've had some of your questions answered and those will lead to more. Or the light will come on and the haze will clear.
 
Hi, Ann.

I must say I support all of Tom's comments. Using AI is (IMHO) absolutely essential ... not optional. Every production database should use AI - otherwise you are always exposed to the risk of losing big chunks of your data in the event of a failure of some sort.

It is SO important, in fact, that you probably do need a professional consultant to help you set it up properly - and to explain-away the 'haze'. It isn't really that complex at all - although it may seem that way when you first look at it.

Ron.
 
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