[Swift-devel] Coaster capabilities for release 0.9

[Ian Foster]

Yes, perhaps the automated system should be default. I don't feel  
strongly about that.


On Apr 22, 2009, at 11:16 AM, Mihael Hategan wrote:

> On Wed, 2009-04-22 at 10:49 -0500, Ian Foster wrote:
>>>>>
>>>>>
>>>>> What you say does beg for a couple of questions:
>>>>> - if all work is done in a run but the allocation has more time
>>>>> left,
>>>>> should the workers be shut down or not?
>>
>>
>> Shut down.
>
> Ok.
>
>>
>>>>>
>>>>> - if more work remains to be done in a run after an explicit
>>>>> allocation
>>>>> was used, should the system attempt to allocate more nodes? If
>>>>> not,
>>>>> should it hang? Fail?
>>
>>
>> Fail.
>
> I disagree. If the user didn't want the work to complete, they  
> wouldn't
> run it. It should be possible to force this mode, but I don't think it
> should be the default.
>
>>
>>>>>
>>>>> - if the allocation is far in the distance from now, and a run
>>>>> is
>>>>> started now, is allocating nodes now a matter of second-guessing
>>>>> or a
>>>>> matter of trying to finish the work faster? What, besides
>>>>> alleged
>>>>> complexity of the algorithm, would be the downside of doing so?
>>
>>
>> Maybe someone has requested an allocation at 10am tomorrow because
>> that is when they want to run the application.
>
> I'd assume then that they would start swift somewhere around 10am
> tomorrow, not one or two days in advance.
>
>>
>>
>> Maybe they are benchmarking, and want things to run with a specified
>> number of nodes).
>>
>
> Being able to force a "use exactly these nodes for this amount of time
> at this time" is a given. Making it the default I have issue with.
>
>>
>> Maybe someone doesn't trust the clever algorithm, or finds that it
>> fails for odd reason.
>>
>
> Right. Many people don't trust garbage collection either. I find it
> funny that people insist that non-trivial things such as distributed
> computing, GC, special relativity be entirely intuitive.
>
>>
>> Having a more complex algorithm as well is great. I'm not saying this
>> would not be wonderful. But it shouldn't be obligatory.
>
> That's far from the statement of making the other one the default.
>
> Let's ask our users though!
>