[CentOS] OT how to prevent oversubscription of a disk

Tue Jan 4 01:10:28 UTC 2011
Ross Walker <rswwalker at gmail.com>

On Jan 3, 2011, at 2:39 PM, Dave <tdbtdb+centos at gmail.com> wrote:

> On Sat, Jan 1, 2011 at 10:06 PM, Gordon Messmer <yinyang at eburg.com> wrote:
>> On 01/01/2011 05:56 PM, Dave wrote:
>>> Is there a best practice? People have to be doing something!
>> I think that's unlikely.  If you don't "oversubscribe" your disk space
>> as a matter of policy, you'll force upgrades earlier than most people
>> would consider them necessary.  Most users, I'd expect, will be well
>> under quota most of the time.  You'd commit all of your disk space to
>> quota long before the space was actually used.  In your scenario, you'd
>> be required to expand the disk array whenever it was committed to quota,
>> even if actual use was very low.  Every site that I know of which uses
>> quotas handles disk upgrades when utilization requires it, not when
>> quota subscription does.
> So, is it fair to rephrase that as "ignore quotas, pay attention to
> actual usage"?
> I agree that some degree of oversubscription is probably desireable,
> and it would be much easier to just add storage whenever it looks to
> be getting fullish. My situation right now makes that difficult -
> budget is gone, so I can't add storage, and my users sometimes start
> up a big simulation that could potentially fill the disk right before
> the weekend. If the hoggy simulation crashes itself, that's okay, but
> if it brings down a lot of other jobs submitted by other users, I look
> bad. I guess even if there was some good tool support, this task is
> doomed to make everyone unhappy.

Maybe you can have the users run these in containers like OpenVz that are set to clean themselves up after they finish?