problem with large quotas

Sebastian Hagedorn Hagedorn at
Thu Apr 7 05:50:13 EDT 2005


--On 5. April 2005 12:21:41 Uhr -0400 Ken Murchison <ken at> wrote:

>>> Yes, both the quota limit and quota usage are limited to 32-bits.  Cyrus
>>> 2.3 uses 64-bits (long long int) on systems that support it.
>> I wonder if this is still true for 2.2.10. I set my quota to 3 GBs and
>> it seems to work OK:
>>> sq user/a0620 3000000
>> quota:3000000
>>> lq user/a0620
>> STORAGE 297144/3000000 (9.9048%)
>> [cyrus at lvr13 imap]$ quota user/a0620
>>   Quota  % Used    Used Root
>> 3000000       9  297163 user/a0620
>> Am I missing something?
> The limit is measured in Kbytes where the usage is measured in bytes. So,
> while you can theoretically set the limit to 2TB (2GB * 1KB), the usage
> is still limited to 2GB (32 bits).  Did I explain this clearly? Reading
> it myself, I'm not sure I did.  ;)

I'm glad you wrote that, because I'm not sure I understand ;-) I get the 
difference between limit and usage. What I don't get is when precisely this 
becomes an issue. If I've got a limit > 2 GB all usages up to 2 GB should 
be OK, because neither value overflows its variable, right? If the usage 
goes over the 2 GB limit, I assume it would roll over? So the worst case 
scenario would be that quotas > 2GB equal no quota!?

But this analysis does not mesh with the following statement:

>>> I set a user to have a 10 gigabyte quota and the user was treated as
>>> being  over-quota with just 10 megabytes.

How does that happen? Is it that the difference between limit and usage is 
measured in bytes and is also 32 bits? That might explain it ...

Thanks, Sebastian Hagedorn
Sebastian Hagedorn - RZKR-R1 (Gebäude 52), Zimmer 18
Zentrum für angewandte Informatik - Universitätsweiter Service RRZK
Universität zu Köln / Cologne University - Tel. +49-221-478-5587
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 194 bytes
Desc: not available
Url :

More information about the Info-cyrus mailing list