Re: [Condor-users] kill exprs with job props

[Derek Wright <wright@xxxxxxxxxxx>]

On Mon, 5 Dec 2005 15:57:05 -0500 (EST)  Douglas L Thain wrote:

> I want to do something like this:
> PREEMPT = ( if suspended ) && ( suspend time > JobMaxSuspend )
> Where JobMaxSuspend is defined in the *job's* classad.

right.  no problem with that.

> Different users have different tolerances for suspension,
> so changing the machine's default suspend time doesn't help me.

that's why you're referring to a job attribute.  that's how these
policy expressions were designed... you can refer to attributes from
either the machine or the job without doing anything special.

> Is there any hidden difficulty here?
> 
> The only wrinkles that I see are:
> 
> A - Users may decline to define +JobMaxSuspend=n in their submit files.
>     This can be addressed by adding to SUBMIT_EXPRS in the local environment.
>     Flocked users will run into trouble if they haven't defined it.

you could probably get it to use "(JobMaxSuspend =?= UNDEFINED)" to
avoid these troubles.  something like:

PREEMPT = (if suspended) && 
(  ((JobMaxSuspend =!= UNDEFINED) && (suspend time > JobMaxSuspend))
|| ((JobMaxSuspend =?= UNDEFINED) && (suspend time > ConfigMaxSuspend)) )

that way, you don't have to worry about SUBMIT_EXPRS or flocking.

> B - Users can "cheat" by defining arbitrarily long JobMaxSuspend times.
>     To solve this, we need max() and min(), which require ?: conditionals
>     from NewClassAds.  However, the effects of such "cheating" are
>     minimal (swap space and a few pids consumed) and can be monitored
>     administratively.

indeed.

> Did I get that right, or is there something else to worry about?

seems you got it right.  i can't think of any other problems...

good luck,
-derek