Re: Elastic Quota File System (EQFS)

From: Fao, Sean
Date: Fri Jun 25 2004 - 09:27:31 EST


Amit Gud wrote:

Hi all,



On one school server, theres 10MB quota. (Okay, its admins are
BOFHs^H^H^H^H^HSISAL). Everyone tries to run mozilla there (because
its installed as default!), and immediately fills his/her quota with
cache files, leading to failed login next time (gnome just will not
start if it can't write to ~).

Imagine mozilla automatically marking cache files "elastic".

That would solve the problem -- mozilla caches would go away when disk
space was demanded, still mozilla's on-disk caching would be effective
when there is enough disk space.



Also this is applicable to mailboxes - automize the marking of old mails of
the mailing list as elastic, whenever the threshold is reached, you might
either want to put those mails as compressed archive or simply delete it.
This has two advantages:
- No email bounces for the reason of 'mailbox full' and
- Optimized utlization of the mailbox

Yes, this can be done using scripts too, but what if you are to use other
users' space that they are not using? Of course script cannot do that! You
need to have some FS support or a libquota hack.


What you're suggesting is not something that could be controlled by the file system because there are far too many methods for storing email. Consider, for instance, if all email messages are stored in a single database file. Unless you include parsing code for all email storage methods, there's no possible way for your design to work. As you should be able to see, this "feature" should be implemented in the email server code; *not* the file system.

Personally, I would rather not use this feature, at all; but, I'm also entitled to leaving the elastic bit turned off on all my messages.

Sean
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