Adjusting Historical Stat Database Durations

[Milesprower]

Has anyone experience with adjusting the historical duration parameters on a live system?

I normally set up new systems so when I adjust them with the customer, there is no impact.

However, I am working on a release 4.2 system that is 24x7. I need to adjust the number of Applications up from 10-15, but the Historical database required size has grown to be larger than its actual size.

So now I am working with the customer to lower the daily and interval duration to get the required size down below the actual size.

I did this on another (release 4,2) live system two years ago and ended up losing data for that day. Is this still an issue?

My guess is that database resizes when daily processing is kicked off @ midnight. As my customer is 24x7 they are concerned about losing data.

I have not found anything in the documentation that addresses issues with reducing the size of the database.

 

[sandyml]

Well, you are correct. And if you think about it a bit, how else would it work? If you reduce the parameters in one area, then at the midnight purge, it would eliminate anything that exceeded the new thresholds.

 

[sandyml]

I have to apologize for the smarta** tone of my reply, I didn't really intend to come across that way.

At any rate, you'll find the documentation on this issue in the Administrators Guide (297-2183-922):

Removal of expired statistics

Each day, the server deletes any historical data that has exceeded the allowable
age for data of its type (defined on the Duration property page of the Historical
Statistics Configuration window). If the size of the statistics database exceeds
the size configured during installation, then the server deletes the oldest
unexpired data to provide space for new data.

 

[Milesprower]

No harm:

My bad experience is that I lost that days data when I shortened the database duration for daily stats. It was a Saturday and I lost that Saturday's data. That is why I asked if anyone had experience on a live system. The system I am working on now has been in service ~ 3 years.

The admin guide is typically vague: it does not say anything about losing data when adjusting the database duration. It also does not address the Reset button which now appears on the Web Client. Does this button reset parameters to default values or the last submitted values?