resource maps

[Gustavo Niemeyer]

On Mon, May 21, 2012 at 12:52 PM, William Reade
<william.reade at canonical.com> wrote:
>> I actually find such a precedence setting attractive. It allows us to
>> define ordering so that conflicts may be solved (is it cheaper to run
>> 2 CPU + 2048 GB of memory or 4 CPU + 1024 GB of memory?) without
>> attempting to get onto cost issues. Such a weighting value will remain
>> valid for longer, while prices devalue and get out of date with time
>> (AWS prices change somewhat frequently).
>
> I don't think I was quite clear about cost: it's intended more as a
> measure of relative opportunity cost than of actual currency. So, it's
> convenient but coincidental that it happens to map onto USDph in the
> example given.

A "cost" setting that "happens to map to USD" feels like a weak
concept that will certainly be misunderstood and misused. We could
solve the problem with a "precedence" setting which is an integer that
defines ordering, and document it as such.

> Field precedence strikes me as a little bit restrictive; I might easily
> favour take 2+2048 over 4+1024, but that doesn't imply that 2+65536

That's exactly what I was pointing out above. I didn't mean "field
precedence", but "precedence field".


gustavo @ http://niemeyer.net