[Kolab-devel] (fwd) how to deal with quotas / suggested feature "monthly quota increase"

[Jeroen van Meeuwen (Kolab Systems)]

Gunnar Wrobel wrote:
> Zitat von "Jeroen van Meeuwen (Kolab Systems)" <vanmeeuwen at kolabsys.com>:
> > 2) Adjust the LDAP quota setting for the users.
> >
> > 2.a) Using some formula that is in a configuration file somewhere;
> > 2.b) Use the updated values in the report
> >
> 
> I definitely like it. I would probably skip the bonus points :) but  
> thats not important. A question I would have concerning 2.a): Gavin  
> required two attributes for his approach. Within 2.2.4 we can use  
> cyrus-userquota for one of them but where does the %-increase  
> information come from?
> 

Which two attributes would that be?

One is the interval, which;

- Either directly aligns with the cronjob run interval, or

- Requires additional tracking of "latest update timestamp"

The other one is the actual formula:

Q($cq) = ($cq * $percent-float) + ($cq + $static)

Where:

- $cq is the current quota value,
- $percent-float is ($conf-value / 100) || 0
- $static is a static increase in MB, configurable of course

If you run it every first of the month, you have a predictable trend without 
tracking when the latest update had been made.

If you run it every day, then you need the intended interval hidden in such 
function or in the code/config somewhere, but, more significantly, you would 
also need to track when the latest quota increase on each account had been 
made; either with an LDAP attribute, major code changes, or in a local 
database.

What the code running once a month can more easily do by itself, however, is 
take the old quota value and compare it to the current usage percentage, to 
see if it matches a threshold or not; it doesn't require additional tracking 
of transactional data.

Kind regards,

-- 
Jeroen van Meeuwen
Senior Engineer, Kolab Systems AG

e: vanmeeuwen at kolabsys.com
t: +316 42 801 403
w: http://www.kolabsys.com

pgp: 9342 BF08